Patent Application
20240368366
There is a well-known global issue with waste disposal, particularly of large volume consumer products such as plastics or polymers that are not considered biodegradable within acceptable temporal limits. There is a public desire to incorporate these types of wastes into renewed products through recycling, reuse, or otherwise reducing the amount of waste in circulation or in landfills. This is especially true for single-use plastic articles/materials.
As consumer sentiment regarding the environmental fate of single-use plastics, such as straws, cutlery, to-go cups, and plastic bags, are becoming a global trend, plastics bans are being considered/enacted around the world in both developed and developing nations. Bans have extended from plastic shopping bags into straws, cutlery, clamshell packaging, and expanded polystyrene foam for example, in the U.S. alone. Other countries have taken even more extreme steps, such as the list of ten single-use articles slated to be banned, restricted in use, or mandated to have extended producer responsibilities throughout the EU. As a result, industry leaders, brand owners, and retailers have made ambitious commitments to implement recyclable, reusable or compostable packaging in the coming years. While recyclable materials are desirable in some applications, other applications lend themselves better to materials that are compostable and/or biodegradable, such as when the article is contaminated with food or when there are high levels of leakage into the environment due to inadequate waste management systems.
Use of biodegradable and/or compostable materials in the manufacture of such single-use articles, though highly desirable from an environmental perspective, presents particular problems for article manufacturers. Most such articles have been manufactured historically using non-biodegradable, fossil fuel-based materials and employ melt processing techniques such as casting, extrusion and injection molding, wherein the material is melted into flowable form, processed and cooled to form a functional article. Utilizing biodegradable raw material, such as some cellulose acetates, in existing manufacturing systems without significant equipment replacement, modification or retrofit costs is difficult. Further, changes in processing conditions that may be necessitated by use of biodegradable materials can negatively impact efficiency and material yields. In addition, many biodegradable raw material alternatives to date have simply fallen short of fossil fuel-based options in terms of end-use article performance and life span. For example, the melt-processing steps for converting cellulose acetate to useful articles can require heating the cellulose acetate to temperatures that may slowly result in color formation as well as a loss in molecular weight of the polymer that can affect the heat stability of the final article.
There is an unmet market need for single-use consumer products that have adequate performance and melt-processing properties for their intended use and that are compostable and/or biodegradable.
It would also be beneficial to provide products having such properties and that also have significant content of renewable, recycled, and/or re-used material.
Applicants have unexpectedly discovered that certain melt-stable cellulose acetates are surprisingly advantageous for use in formulated thermal processing. In stabilized form, they exhibit reduced undesirable color formation during extrusion and thermoforming and in formulations or compositions exhibit minimal if any molecular weight reduction.
In a first aspect, the present invention is directed to a biodegradable melt-stable cellulose acetate. The biodegradable melt-stable cellulose acetate of the present invention may be characterized by a heated intrinsic viscosity (HIV) of at least 0.9.
In another aspect, the present invention is directed to a melt-processable, biodegradable melt-stable cellulose acetate. The melt-processable, biodegradable melt-stable cellulose acetate of the present invention may be characterized by a metals-to-sulfur molar ratio
M/S
of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium, sodium and combinations thereof and S is moles sulfur.
In another aspect, the present invention is directed to a melt-processable, biodegradable, cellulose acetate composition. The melt-processable, biodegradable, cellulose acetate composition of the present invention includes (i) a biodegradable melt-stable cellulose acetate characterized by a heated intrinsic viscosity (HIV) of at least 0.9 and (ii) a plasticizer.
In another aspect, the present invention is directed to a melt-processable, biodegradable, cellulose acetate composition. The melt-processable, biodegradable, cellulose acetate composition of the present invention includes (i) a biodegradable, melt-stable cellulose acetate characterized by a metals-to-sulfur molar ratio
M/S
of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium, sodium and combinations thereof and S is moles sulfur; and (ii) a plasticizer.
In still another aspect, the present invention is directed to a cellulose acetate melt, useful in particular for forming melt processed articles. The cellulose acetate melt of the present invention includes i) a biodegradable melt-stable cellulose acetate characterized by a heated intrinsic viscosity (HIV) of at least 0.9 and (ii) a plasticizer.
In yet another aspect, the present invention is directed to a cellulose acetate melt, useful in particular for forming melt processed articles. The cellulose acetate melt of the present invention includes i) a biodegradable, melt-stable cellulose acetate characterized by a metals-to-sulfur molar ratio M/S of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium, sodium and combinations thereof and S is moles sulfur; and (ii) a plasticizer.
In yet another aspect, the present invention is directed to a melt-formed article. The melt-formed article of the present invention is formed from a cellulose acetate melt of the present invention that includes i) a biodegradable, melt-stable cellulose acetate characterized by a heated intrinsic viscosity (HIV) of at least 0.9 and (ii) a plasticizer or includes a cellulose acetate composition of the present invention that includes (i) a biodegradable, melt-stable cellulose acetate characterized by a heated intrinsic viscosity (HIV) of at least 0.9 and (ii) a plasticizer.
In yet another aspect, the present invention is directed to a melt-formed article. The melt-formed article of the present invention is formed from a cellulose acetate melt of the present invention that includes i) a biodegradable, melt-stable stabilized cellulose acetate characterized by a metals-to-sulfur molar ratio
M/S
of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium, sodium and combinations thereof and S is moles sulfur; and (ii) a plasticizer.
The present application also discloses additional compositions, articles, and methods in various aspects.
In a first aspect, the present invention is directed to a biodegradable, melt stable cellulose acetate. In one or more embodiments, the biodegradable, melt-stable cellulose acetate of the present invention may be characterized by a heated intrinsic viscosity (HIV) of at least 0.9. In one or more embodiments, the biodegradable, melt-stable cellulose acetate of the present invention may be characterized by a metals-to-sulfur molar ratio
M/S
of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium, sodium and combinations thereof and S is moles sulfur.
Cellulose acetates that may be useful for the present invention generally comprise repeating units of the structure:
wherein R1, R2, and R3 are selected independently from the group consisting of hydrogen or acetyl. For cellulose esters, the substitution level is usually express in terms of degree of substitution (DS), which is the average number of non-OH substituents per anhydroglucose unit (AGU). Generally, conventional cellulose contains three hydroxyl groups in each AGU unit that can be substituted; therefore, DS can have a value between zero and three. Native cellulose is a large polysaccharide with a degree of polymerization from 250-5,000 even after pulping and purification, and thus the assumption that the maximum DS is 3.0 is approximately correct. Because DS is a statistical mean value, a value of 1 does not assure that every AGU has a single substituent. In some cases, there can be unsubstituted anhydroglucose units, some with two and some with three substituents, and typically the value will be a non-integer. Total DS is defined as the average number of all of substituents per anhydroglucose unit. The degree of substitution per AGU can also refer to a particular substituent, such as, for example, hydroxyl or acetyl. In embodiments, n is an integer in a range from 25 to 250, or 25 to 200, or 25 to 150, or 25 to 100, or 25 to 75.
In embodiments of the invention, the cellulose acetates have at least 2 anhydroglucose rings and can have between at least 50 and up to 5,000 anhydroglucose rings, or at least 50 and less than 150 anhydroglucose rings. The number of anhydroglucose units per molecule is defined as the degree of polymerization (DP) of the cellulose acetate. In embodiments, cellulose esters can have an inherent viscosity (IV) of about 0.2 to about 3.0 deciliters/gram, or about 0.5 to about 1.8, or about 1 to about 1.5, as measured at a temperature of 25° C. for a 0.25 gram sample in 100 ml of a 60/40 by weight solution of phenol/tetrachloroethane. In embodiments, cellulose acetates useful herein can have a DS/AGU of about 1 to about 2.5, or 1 to less than 2.2, or 1 to less than 1.5, and the substituting ester is acetyl.
In one or more embodiments, the cellulose acetate is a melt-stable cellulose acetate. The phrase “melt-stable” is intended to describe biodegradable cellulose acetates characterized by one or both of (i) a heated intrinsic viscosity (HIV) of at least 0.9 and/or (ii) a metals-to-sulfur molar ratio
M/S
of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium and sodium and S is moles sulfur. A stabilization treatment may be employed as a separate step prior to forming a melt-processable biodegradable cellulose acetate composition that includes the melt-stable cellulose acetate as a component. In general, a melt-stable cellulose acetate may for example be further treated with one or more stabilizers such as for example C3 to C5 hydroxy acids.
Cellulose acetates compositions and melts useful in the present invention are melt-processable. The phrase “melt-processable” is intended to describe or include materials which generally exist in a solid form at ambient/room temperature and transition to and form a flowable melt with exposure to an elevated temperature (generally referred to a melt temperature), with the resulting flowable melt (typically in a formulation or composition form) processable using conventional melt-formed article formation processes such as injection molding, blow molding, extrusion, profiling, foaming, casting and the like as described herein or generally known in the art.
Cellulose acetates and melt-stable cellulose acetates useful in the present invention are biodegradable. The term “biodegradable” generally refers to the biological conversion and consumption of organic molecules. Biodegradability is an intrinsic property of the material itself, and the material can exhibit different degrees of biodegradability, depending on the specific conditions to which it is exposed. The term “disintegrable” refers to the tendency of a material to physically decompose into smaller fragments when exposed to certain conditions. Disintegration depends both on the material itself, as well as the physical size and configuration of the article being tested. Ecotoxicity measures the impact of the material on plant life, and the heavy metal content of the material is determined according to the procedures laid out in a standard test method.
Cellulose acetates of the present invention can be produced by any method known in the art. Examples of processes for producing cellulose esters generally are taught in Kirk-Othmer, Encyclopedia of Chemical Technology, 5th Edition, Vol. 5, Wiley-Interscience, New York (2004), pp. 394-444. Cellulose, the starting material for producing cellulose acetates, can be obtained in different grades and sources such as from cotton linters, softwood pulp, hardwood pulp, corn fiber and other agricultural sources, and bacterial cellulose, among others.
One method of producing cellulose acetates is esterification of the cellulose by mixing cellulose with the appropriate organic acids, acid anhydrides, and catalysts. Cellulose is then converted to a cellulose triester. Ester hydrolysis is then performed by adding a water-acid mixture to the cellulose triester, which can then be filtered to remove any gel particles or fibers. Water is then added to the mixture to precipitate the cellulose ester. The cellulose ester can then be washed with water to remove reaction by-products followed by dewatering and drying.
The cellulose triesters to be hydrolyzed can have three acetyl substituents. These cellulose esters can be prepared by a number of methods known to those skilled in the art. For example, cellulose esters can be prepared by heterogeneous acylation of cellulose in a mixture of carboxylic acid and anhydride in the presence of a catalyst such as H2SO4. Cellulose triesters can also be prepared by the homogeneous acylation of cellulose dissolved in an appropriate solvent such as LiCI/DMAc or LiCI/NMP.
Those skilled in the art will understand that the commercial term of cellulose triesters also encompasses cellulose esters that are not completely substituted with acyl groups. For example, cellulose triacetate commercially available from Eastman Chemical Company, Kingsport, TN, U.S.A., typically has a DS from about 2.85 to about 2.99.
After esterification of the cellulose to the triester, part of the acyl substituents can be removed by hydrolysis or by alcoholysis to give a secondary cellulose ester. As noted previously, depending on the particular method employed, the distribution of the acyl substituents can be random or non-random. Secondary cellulose esters can also be prepared directly with no hydrolysis by using a limiting amount of acylating reagent. This process is particularly useful when the reaction is conducted in a solvent that will dissolve cellulose. All of these methods yield cellulose esters that are useful in this invention.
In one embodiment or in combination with any of the mentioned embodiments, or in combination with any of the mentioned embodiments, the cellulose acetates of the present invention are cellulose diacetates. The cellulose diacetates may have a polystyrene equivalent number average molecular weight (Mn) from about 10,000 to about 100,000 as measured by gel permeation chromatography (GPC) using NMP as solvent and polystyrene equivalent Mn according to ASTM D6474. In other aspects or embodiments of the present invention described herein, the melt-processable, biodegradable cellulose acetate composition of the present invention includes cellulose diacetate having a polystyrene equivalent number average molecular weights (Mn) from 10,000 to 90,000; or 10,000 to 80,000; or 10,000 to 70,000; or 10,000 to 60,000; or 10,000 to less than 60,000; or 10,000 to less than 55,000; or 10,000 to 50,000; or 10,000 to less than 50,000; or 10,000 to less than 45,000; or 10,000 to 40,000; or 10,000 to 30,000; or 20,000 to less than 60,000; or 20,000 to less than 55,000; or 20,000 to 50,000; or 20,000 to less than 50,000; or 20,000 to less than 45,000; or 20,000 to 40,000; or 20,000 to 35,000; or 20,000 to 30,000; or 30,000 to less than 60,000; or 30,000 to less than 55,000; or 30,000 to 50,000; or 30,000 to less than 50,000; or 30,000 to less than 45,000; or 30,000 to 40,000; or 30,000 to 35,000; as measured by gel permeation chromatography (GPC) using NMP as solvent and according to ASTM D6474.
The most common commercial secondary cellulose esters are prepared by initial acid catalyzed heterogeneous acylation of cellulose to form the cellulose triester. After a homogeneous solution in the corresponding carboxylic acid of the cellulose triester is obtained, the cellulose triester is then subjected to hydrolysis until the desired degree of substitution is obtained. After isolation, a random secondary cellulose ester is obtained. That is, the relative degree of substitution (RDS) at each hydroxyl is roughly equal.
In embodiments of the invention, the cellulose acetate can be prepared by converting cellulose to a cellulose ester with reactants that are obtained from recycled materials, e.g., a recycled plastic content syngas source. In embodiments, such reactants can be cellulose reactants that include organic acids and/or acid anhydrides used in the esterification or acylation reactions of the cellulose, e.g., as discussed herein
The melt-stable cellulose acetates of the present invention may be produced in any physical form that is desirable for downstream processing into compositions, melts and useful articles. In one or more embodiments, the biodegradable melt-stable cellulose acetate is in the form of a powder. In one or more embodiments, the biodegradable melt-stable cellulose acetate is in the form of a flake or pellet.
In one or more embodiments or aspects, biodegradable cellulose acetates of the present invention may be characterized by a heated intrinsic viscosity (also referred to herein as HIV) of at least 0.9 or at least 1.0 or at least 1.05 or at least 1.1 or at least 1.15 or at least 1.2 or at least 1.25 or at least 1.3 or at least 1.35 or at least 1.4 or at least 1.45 or at least 1.5 or at least 1.55 or at least 1.6 or at least 1.65. In one or more embodiments, melt-processable, biodegradable cellulose acetates of the present invention may be characterized by a heated intrinsic viscosity (HIV) of between 1.0 and 2.0 or between 1.1 and 1.8 or between 1.15 and 1.75 or between 1.15 and 1.7 or between 1.2 and 1.7. In embodiments, the melt-processable, biodegradable cellulose acetate has an HIV in a range from 1.15 to 1.7, or 1.2 to 1.7, or 1.25 to 1.7, or 1.3 to 1.7. Heated intrinsic viscosity, in general, is a parameter used in the art to characterize a material's melt flow characteristics. HIV may be measured in a method similar to ASTM method D 871-91 but with a heated protocol. In such a protocol, a weighed amount of sample is heat treated at an initial heat temperature of 50° C. and held for 3 minutes. The temperature is then ramped at a rate of 20 degrees per minute (DPM) until 250° C. is reached and held for 3 minutes. Post treatment, the sample is allowed to cool and then added to acetone to form solution having a concentration of 0.50 g/dL. The relative viscosity is then measured using the solution at 30° C. using a Viscotek Y501C automated viscometer and the intrinsic viscosity is calculated using the Solomon-Gatesman equation with units of dL/g.
In one or more embodiments or aspects, biodegradable melt-stable composition comprises cellulose acetates that may be characterized by a heated intrinsic viscosity (also referred to herein as HIV) of at least 0.9 or at least 1.0 or at least 1.05 or at least 1.1 or at least 1.15 or at least 1.2 or at least 1.25 or at least 1.3 or at least 1.35 or at least 1.4 or at least 1.45 or at least 1.5 or at least 1.55 or at least 1.6 or at least 1.65. In one or more embodiments, melt-processable, biodegradable stabilized cellulose acetates of the present invention may be characterized by a heated intrinsic viscosity (HIV) of between 1.0 and 2.0 or between 1.1 and 1.8 or between 1.15 and 1.75 or between 1.15 and 1.7 or between 1.2 and 1.7. In embodiments, the melt-processable, biodegradable stabilized cellulose acetate has an HIV in a range from 1.15 to 1.7, or 1.2 to 1.7, or 1.25 to 1.7, or 1.3 to 1.7. Heated intrinsic viscosity, in general, is a parameter used in the art to characterize a material's melt flow characteristics. HIV may be measured according to the method described above.
The biodegradable melt-stable cellulose acetates of the present invention may also be described using other characterizations or parameters. In one or more embodiments, biodegradable melt-stable cellulose acetates of the present invention may be characterized by a color value (b*) of less than 40, or less than 35, or less than 30, or less than 25, or less than 20, or less than 10. The parameter b* is a known component of the CIE L*a*b* color measurement technique as described for example in ASTM D 6290-98 and ASTM E308-99. Low color values and color stability are often desirable by manufacturers and purchasers of melt-formed articles. In one or more embodiments, biodegradable melt-stable cellulose acetates of the present invention may be characterized by a color value (b*) of less than 40, or less than 35, or less than 30, or less than 25, or less than 20, or less than 10.
In one or more embodiments, biodegradable, melt-stable cellulose acetates of the present invention may be characterized by metal content by ICP. The ICP method is carried out where an ester sample is prepared by digesting 1 g of ester in 10 mL of trace-metal grade nitric acid (HNO3). Digestion is carried out for 1 hour. The digested sample is then treated by adding 1 mL internal standard and diluting the mixture to 100 mL total with high purity water. The Internal Standard Solution contains 10,000 μg/mL (ppm) Be, Sc, and Y (CASRN 7440-65-5) in 2% HNO3. The sample is then pumped into an Inductively Coupled Plasma—Optical Emission Spectrometer, which is generating an argon plasma. The plasma atomizes and excites elements present in the sample. The resulting emission from the excited state is detected and used to quantify the concentration of those elements in solution based on comparison of the response to that of standards of known concentration.
For example, biodegradable melt-stable cellulose acetates of the present invention may be characterized by one or more of the following: (i) a calcium content of less than 50 ppm; (ii) a magnesium content of less than 15 ppm; (iii) a sodium content of at least 5 ppm; and (iv) a sulfur content of at least 55 ppm. Applicants have unexpectedly discovered that the described metal contents, alone or in combination, may improve melt processability by maintaining the molecular weight, or by minimizing molecular weight reduction, during melt processing. In embodiments, the cellulose acetate has a calcium content from 0 to 50, or 0 to 45 ppm; a magnesium content from 0 to 20, or 0 to 15, or 0 to 14 ppm; a sodium content from 2 to 250, or 2 to 240, or 5 to 240 ppm; a potassium content of 0 to 15, or 0 to 10 ppm; and a sulfur content of 50 to 250, or 55 to 240, or 55 to 230 ppm.
In one or more embodiments, the biodegradable melt-stable cellulose acetates of the present invention, when in powder form, may be characterized by a bulk density of at least 25 lb/cu·ft, or at least 30 lb/cu·ft. or from 25 lb/cu·ft to 40 lb/cu·ft. or from 30 lb/cu·ft to 40 lb/cu·ft. or no more than 40 lb/cu·ft. Bulk density values may be determined according to ASTM D7481-09 or using a procedure where the cellulose acetate is poured into a tared graduated cylinder to the 100 mL mark. The weight of ester and the volume are used to calculate the bulk density in pounds per cubic foot.
In one or more embodiments, biodegradable, melt-stable cellulose acetates of the present invention, when in powder form, may be characterized by a surface area of at least 4 m2/g or at least 5 m2/g, or at least 9 m2/g. of from 4 m2/g to 20 m2/g or from 5 m2/g to 20 m2/g or from 9 m2/g to 20 m2/g or no more than to 20 m2/g. Surface area values may be measured using conventional equipment such as a Micromeritics BET Analyzer (Model ASAP2020) generating BET surface area values and Langmuir surface area values.
In one or more embodiments, melt processable, biodegradable cellulose acetates of the present invention as well as the melt processable, biodegradable stabilized cellulose acetates of the present invention may be characterized by a fiber count of at least 50 or at least 70 or from 50 to 500 or from 70 to 500 or no more than 500. The phrase “fiber count”, in general, is used to assess or evaluate residual particulate solids content of cellulose acetate after its manufacture. Fiber count is measured on cellulose ester dopes that are prepared at 8% solids in a solvent mixture comprised of 90/10 (W/W) dichloromethane/methanol. After dissolution, the sample is poured into a 20-mm path length quartz cell. The sample is then analyzed by an imaging system capable of capturing and counting the images of the birefringent insoluble fibers. Applicants have surprisingly discovered that the above-described fiber counts unexpectedly translate to improved melt processability.
One of ordinary skill will appreciate that the material characterizations, elements and features described above with respect to the biodegradable melt-stable cellulose acetates of the present invention are also applicable and useful to characterize the melt-processable, biodegradable, cellulose acetate compositions, melts, and articles described herein. Accordingly, the descriptions for these characterizations, elements and features are expressly relied on to support and describe the elements and features of all aspects of the present invention described herein. More generally, the descriptions for characterizations, elements and features of one aspect are expressly relied on to support and describe those elements and features with regard to all aspects of the present invention described herein.
In another aspect, the present invention is directed to a melt-processable, biodegradable, cellulose acetate composition. In one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention includes (i) a biodegradable melt-stable cellulose acetate characterized by a heated intrinsic viscosity (HIV) of at least 0.9 and (ii) a plasticizer. In one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention includes (i) a biodegradable, melt-stable cellulose acetate characterized by a metals-to-sulfur molar ratio
M/S
of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium, sodium and combinations thereof and S is moles sulfur; and (ii) a plasticizer. In embodiments, the cellulose acetate has a metals-to-sulfur ratio of 1.35 to 10.0, or 1.35 to 8.0, or 1.35 to 6.0, or 1.35 to 5.0, or 1.4 to 10.0, or 1.4 to 8.0, or 1.4 to 6.0, or 1.4 to 5.0, or 1.45 to 10.0, or 1.45 to 8.0, or 1.45 to 6.0, or 1.45 to 5.0, or 1.5 to 10.0, or 1.5 to 8.0, or 1.5 to 6.0, or 1.5 to 5.0.
In embodiments, the cellulose acetate composition comprises, biodegradable melt-stable cellulose acetate (also referred to herein from time to time as BCA) and at least one plasticizer. The plasticizer reduces the melt temperature, the Tg, and/or the melt viscosity of the cellulose acetate. In embodiments, the plasticizer is a food-compliant plasticizer. By food-compliant is meant compliant with applicable food additive and/or food contact regulations where the plasticizer is cleared for use or recognized as safe by at least one (national or regional) food safety regulatory agency (or organization), for example listed in the 21 CFR Food Additive Regulations or otherwise Generally Recognized as Safe (GRAS) by the US FDA. In embodiments, the food-compliant plasticizer is triacetin. In embodiments, examples of food-compliant plasticizers that could be considered can include triacetin, triethyl citrate, glycerol esters (e.g., tripropionin, tributyrin, or tribenzoin), polyethylene glycol, Benzoflex, propylene glycol, polysorbatemsucrose octaacetate, acetylated triethyl citrate (e.g., acetyl triethyl citrate), acetyl tributyl citrate, Admex, tripropionin, Scandiflex, poloxamer copolymers, polyethylene glycol succinate, diisobutyl adipate, polyvinyl pyrollidone, and glycol tribenzoate.
In embodiments, the plasticizer can be present in an amount sufficient to permit the melt-processable, biodegradable cellulose acetate composition to be melt processed (or thermally formed) into useful articles, e.g., single use plastic articles, in conventional melt processing equipment. In embodiments, the plasticizer may be present in an amount from 1 to 40 wt % for most thermoplastics processing; or 15 to 25 wt %, or 13-17 wt % for profile extrusion; or 19-22 wt % for sheet extrusion; or 23-27 wt % for injection molding, each based on the weight of the cellulose acetate composition. In embodiments, profile extrusion, sheet extrusion, thermoforming, and injection molding can be accomplished with plasticizer levels in the 13-30, or 13-25, or 15-30, or 15-25 wt % range, based on the weight of the cellulose acetate composition. In embodiments, the cellulose acetate composition comprises at least one plasticizer (as described herein) in an amount from 1 to 40 wt %, or 5 to 40 wt %, or 10 to 40 wt %, or 13 to 40 wt %, or 15 to 40 wt %, or greater than 15 to 40 wt %, or 17 to 40 wt %, or 20 to 40 wt %, or 25 to 40 wt %, or 5 to 35 wt %, or 10 to 35 wt %, or 13 to 35 wt %, or 15 to 35 wt %, or greater than 15 to 35 wt %, or 17 to 35 wt %, or 20 to 35 wt %, or 5 to 30 wt %, or 10 to 30 wt %, or 13 to 30 wt %, or 15 to 30 wt %, or greater than 15 to 30 wt %, or 17 to 30 wt %, or 5 to 25 wt %, or 10 to 25 wt %, or 13 to 25 wt %, or 15 to 25 wt %, or greater than 15 to 25 wt %, or 17 to 25 wt %, or 5 to 20 wt %, or 10 to 20 wt %, or 13 to 20 wt %, or 15 to 20 wt %, or greater than 15 to 20 wt %, or 17 to 20 wt %, or 5 to 17 wt %, or 10 to 17 wt %, or 13 to 17 wt %, or 15 to 17 wt %, or greater than 15 to 17 wt %, or 5 to less than 17 wt %, or 10 to less than 17 wt %, or 13 to less than 17 wt %, or 15 to less than 17 wt %, all based on the total weight of the cellulose acetate composition. In embodiments, the cellulose acetate composition further comprises at least one filler (as described herein) in an amount from 1 to 60 wt %, or 5 to 55 wt %, or 5 to 50 wt %, or 5 to 45 wt %, or 5 to 40 wt %, or 5 to 35 wt %, or 5 to 30 wt %, or 5 to 25 wt %, or 10 to 55 wt %, or 10 to 50 wt %, or 10 to 45 wt %, or 10 to 40 wt %, or 10 to 35 wt %, or 10 to 30 wt %, or 10 to 25 wt %, or 15 to 55 wt %, or 15 to 50 wt %, or 15 to 45 wt %, or 15 to 40 wt %, or 15 to 35 wt %, or 15 to 30 wt %, or 15 to 25 wt %, or 20 to 55 wt %, or 20 to 50 wt %, or 20 to 45 wt %, or 20 to 40 wt %, or 20 to 35 wt %, or 20 to 30 wt %, all based on the total weight of the cellulose acetate composition. In embodiments, the at least one plasticizer includes or is a food-compliant plasticizer. In one or more embodiments, the food-compliant plasticizer includes or is triacetin. In one or more embodiments, the filler includes or is calcium carbonate.
In embodiments, the plasticizer is a biodegradable plasticizer. Some examples of biodegradable plasticizers include triacetin, triethyl citrate, acetyl triethyl citrate, polyethylene glycol, the benzoate containing plasticizers such as the Benzoflex™ plasticizer series, poly (alkyl succinates) such as poly (butyl succinate), polyethersulfones, adipate based plasticizers, soybean oil epoxides such as the Paraplex™ plasticizer series, sucrose based plasticizers, dibutyl sebacate, tributyrin, sucrose acetate isobutyrate, the Resolflex™ series of plasticizers, triphenyl phosphate, glycolates, polyethylene glycol, 2,2,4-trimethylpentane-1,3-diyl bis(2-methylpropanoate), and polycaprolactones.
In one embodiment or in combination with any of the mentioned embodiments, or in combination with any of the mentioned embodiments, of the invention, a cellulose acetate composition comprising at least one recycle cellulose acetate is provided, wherein the cellulose acetate has at least one substituent on an anhydroglucose unit (AU) derived from recycled content material, e.g., recycled plastic content syngas
In an aspect, the biodegradable cellulose acetates can be formulated into cellulose acetate compositions with a plasticizer and at least one of a filler, additive, biopolymer, stabilizer, and/or odor modifier. Examples of additives include waxes, compatibilizers, biodegradation promoters, dyes, pigments, colorants, luster control agents, lubricants, anti-oxidants, viscosity modifiers, antifungal agents, anti-fogging agents, heat stabilizers, impact modifiers, antibacterial agents, softening agents, mold release agents, and combinations thereof. It should be noted that the same type of compounds or materials can be identified for or included in multiple categories of components in the cellulose acetate compositions. For example, polyethylene glycol (PEG) could function as a plasticizer or as an additive that does not function as a plasticizer, such as a hydrophilic polymer or biodegradation promotor, e.g., where a lower molecular weight PEG has a plasticizing effect and a higher molecular weight PEG functions as a hydrophilic polymer but without plasticizing effect.
In embodiments, the cellulose acetate composition comprises at least one filler. In embodiments, the filler is of a type and present in an amount to enhance biodegradability and/or compostability. In embodiments, the cellulose acetate composition comprises at least one filler chosen from: carbohydrates (sugars and salts), cellulosic and organic fillers (wood flour, wood fibers, hemp, carbon, coal particles, graphite, and starches), mineral and inorganic fillers (calcium carbonate, talc, silica, titanium dioxide, glass fibers, glass spheres, boronitride, aluminum trihydrate, magnesium hydroxide, calcium hydroxide, alumina, and clays), food wastes or byproduct (eggshells, distillers grain, and coffee grounds), desiccants (e.g. calcium sulfate, magnesium sulfate, magnesium oxide, calcium oxide), alkaline fillers (e.g., Na2CO3, MgCO3), or combinations (e.g., mixtures) of these fillers. In embodiments, the cellulose acetate compositions can include at least one filler that also functions as a colorant additive. In embodiments, the colorant additive filler can be chosen from: carbon, graphite, titanium dioxide, opacifiers, dyes, pigments, toners and combinations thereof. In embodiments, the cellulose acetate compositions can include at least one filler that also functions as a stabilizer or flame retardant
In embodiments, the cellulose acetate composition comprises a biodegradable CA component that comprises at least one BCA and a biodegradable polymer component that comprises at least one other biodegradable polymer (other than the BCA). In embodiments, the other biodegradable polymer can be chosen from polyhydroxyalkanoates (PHAs and PHBs), polylactic acid (PLA), polycaprolactone polymers (PCL), polybutylene adipate terephthalate (PBAT), polyethylene succinate (PES), polyvinyl acetates (PVAs), polybutylene succinate (PBS) and copolymers (such as polybutylene succinate-co-adipate (PBSA)), cellulose esters, cellulose ethers, starch, proteins, derivatives thereof, and combinations thereof. In embodiments, the cellulose acetate composition comprises two or more biodegradable polymers. In embodiments, the cellulose acetate composition contains a biodegradable polymer (other than the BCA) in an amount from 0.1 to less than 50 wt %, or 1 to 40 wt %, or 1 to 30 wt %, or 1 to 25 wt %, or 1 to 20 wt %, based on the cellulose acetate composition. In embodiments, the cellulose acetate composition contains a biodegradable polymer (other than the BCA) in an amount from 0.1 to less than 50 wt %, or 1 to 40 wt %, or 1 to 30 wt %, or 1 to 25 wt %, or 1 to 20 wt %, based on the total amount of BCA and biodegradable polymer. In embodiments, the at least one biodegradable polymer comprises a PHA having a weight average molecular weight (Mw) in a range from 10,000 to 1,000,000, or 50,000 to 1,000,000, or 100,000 to 1,000,000, or 250,000 to 1,000,000, or 500,000 to 1,000,000, or 600,000 to 1,000,000, or 600,000 to 900,000, or 700,000 to 800,000, or 10,000 to 500,000, or 10,000 to 250,000, or 10,000 to 100,000, or 10,000 to 50,000, measured using gel permeation chromatography (GPC) with a refractive index detector and polystyrene standards employing a solvent of methylene chloride. In embodiments, the PHA can include a polyhydroxybutyrate-co-hydroxyhexanoate.
In embodiments, the cellulose acetate composition comprises a biodegradable CA component that comprises at least one BCA and a biodegradable polymer component that comprises at least one other biodegradable polymer (other than the BCA). In embodiments, the other biodegradable polymer can be chosen from polyhydroxyalkanoates (PHAs and PHBs), polylactic acid (PLA), polycaprolactone polymers (PCL), polybutylene adipate terephthalate (PBAT), polyethylene succinate (PES), polyvinyl acetates (PVAs), polybutylene succinate (PBS), cellulose esters, cellulose ethers, starch, proteins, derivatives thereof, and combinations thereof. In embodiments, the cellulose acetate composition comprises two or more biodegradable polymers. In embodiments, the cellulose acetate composition contains a biodegradable polymer (other than the BCA) in an amount from 0.1 to less than 50 wt %, or 1 to 40 wt %, or 1 to 30 wt %, or 1 to 25 wt %, or 1 to 20 wt %, based on the cellulose acetate composition. In embodiments, the cellulose acetate composition contains a biodegradable polymer (other than the BCA) in an amount from 0.1 to less than 50 wt %, or 1 to 40 wt %, or 1 to 30 wt %, or 1 to 25 wt %, or 1 to 20 wt %, based on the total amount of BCA and biodegradable polymer. In embodiments, the at least one biodegradable polymer comprises a PHA having a weight average molecular weight (Mw) in a range from 600,000 to 1,000,000, or 600,000 to 900,000, or 700,000 to 800,000, measured using gel permeation chromatography (GPC) with a refractive index detector and polystyrene standards employing a solvent of methylene chloride. In embodiments, the PHA can include a polyhydroxybutyrate-co-hydroxyhexanoate.
In certain embodiments, the cellulose acetate composition comprises at least one stabilizer. Although it is desirable for the cellulose acetate composition to be composable and/or biodegradable, a certain amount of stabilizer may be added to provide a selected shelf life or stability, e.g., towards light exposure, oxidative stability, or hydrolytic stability. In various embodiments, stabilizers can include: UV absorbers, antioxidants (ascorbic acid, BHT, BHA, etc.), other acid and radical scavengers, epoxidized oils, e.g., epoxidized soybean oil, or combinations thereof. As described herein, the cellulose acetate of the present invention may in one or more embodiments be stabilized with a stabilizer in a separate step to form a melt-stable cellulose acetate.
Antioxidants can be classified into several classes, including primary antioxidant, and secondary antioxidant. Primary antioxidants a generally known to function essentially as free radical terminators (scavengers). Secondary antioxidants are generally known to decompose hydroperoxides (ROOH) into nonreactive products before they decompose into alkoxy and hydroxy radicals. Secondary antioxidants are often used in combination with free radical scavengers (primary antioxidants) to achieve a synergistic inhibition effect and secondary AOs are used to extend the life of phenolic type primary AOs.
“Primary antioxidants” are antioxidants that act by reacting with peroxide radicals via a hydrogen transfer to quench the radicals. Primary antioxidants generally contain reactive hydroxy or amino groups such as in hindered phenols and secondary aromatic amines. Examples of primary antioxidants include BHT, Irganox™ 1010, 1076, 1726, 245, 1098, 259, and 1425; Ethanox™ 310, 376, 314, and 330; Evernox™ 10, 76, 1335, 1330, 3114, MD 1024, 1098, 1726, 120, 2246, and 565; Anox™ 20, 29, 330, 70, IC-14, and 1315; Lowinox™ 520, 1790, 221B46, 22M46, 44B25, AH25, GP45, CA22, CPL,3 HD98, TBM-6, and WSP; Naugard™ 431, PS48, SP, and 445; Songnox™ 1010, 1024, 1035, 1076 CP, 1135 LQ, 1290 PW, 1330FF, 1330PW, 2590 PW, and 3114 FF; and ADK Stab AO-20, AO-30, AO-40, AO-50, AO-60, AO-80, and AO-330.
“Secondary antioxidants” are often called hydroperoxide decomposers. They act by reacting with hydroperoxides to decompose them into nonreactive and thermally stable products that are not radicals. They are often used in conjunction with primary antioxidants. Examples of secondary antioxidants include the organophosphorous (e.g., phosphites, phosphonites) and organosulfur classes of compounds. The phosphorous and sulfur atoms of these compounds react with peroxides to convert the peroxides into alcohols. Examples of secondary antioxidants include Ultranox 626, Ethanox™ 368, 326, and 327; Doverphos™ LPG11, LPG12, DP S-680, 4, 10, S480, S-9228, S-9228T; Evernox™ 168 and 626; Irgafos™ 126 and 168; Weston™ DPDP, DPP, EHDP, PDDP, TDP, TLP, and TPP; Mark™ CH 302, CH 55, TNPP, CH66, CH 300, CH 301, CH 302, CH 304, and CH 305; ADK Stab 2112, HP-10, PEP-8, PEP-36, 1178, 135A, 1500, 3010, C, and TPP; Weston 439, DHOP, DPDP, DPP, DPTDP, EHDP, PDDP, PNPG, PTP, PTP, TDP, TLP, TPP, 398, 399, 430, 705, 705T, TLTTP, and TNPP; Alkanox 240, 626, 626A, 627AV, 618F, and 619F; and Songnox™ 1680 FF, 1680 PW, and 6280 FF.
In embodiments, the cellulose acetate composition comprises at least one stabilizer, wherein the stabilizer comprises one or more secondary antioxidants. In embodiments, the stabilizer comprises a first stabilizer component chosen from one or more secondary antioxidants and a second stabilizer component chosen from one or more primary antioxidants, citric acid or a combination thereof.
In embodiments, the stabilizer comprises one or more secondary antioxidants in an amount in the range of from 0.01 to 0.8, or 0.01 to 0.7, or 0.01 to 0.5, or 0.01 to 0.4, or 0.01 to 0.3, or 0.01 to 0.25, or 0.01 to 0.2, 0.02 to 0.8, or 0.02 to 0.7, or 0.02 to 0.5, or 0.02 to 0.4, or 0.02 to 0.3, or 0.02 to 0.25, or 0.02 to 0.2, or 0.05 to 0.8, or 0.05 to 0.7, or 0.05 to 0.5, or 0.05 to 0.4, or 0.05 to 0.3, or 0.05 to 0.25, or 0.05 to 0.2, or 0.08 to 0.8, or 0.08 to 0.7, or 0.08 to 0.5, or 0.08 to 0.4, or 0.08 to 0.3, or 0.08 to 0.25, or 0.08 to 0.2, in weight percent of the total amount of secondary antioxidants based on the total weight of the composition. In one class of this embodiment, the stabilizer comprises a secondary antioxidant that is a phosphite compound. In one class of this embodiment, the stabilizer comprises a secondary antioxidant that is a phosphite compound and another secondary antioxidant that is DLTDP.
In one subclass of this class, the stabilizer further comprises a second stabilizer component that comprises one or more primary antioxidants in an amount in the range of from 0.05 to 0.7, or 0.05 to 0.6, or 0.05 to 0.5, or 0.05 to 0.4, or 0.05 to 0.3, or 0.1 to 0.6, or 0.1 to 0.5, or 0.1 to 0.4, or 0.1 to 0.3, in weight percent of the total amount of primary antioxidants based on the total weight of the composition. In one subclass of this class, the stabilizer further comprises a second stabilizer component that comprises citric acid in an amount in the range of from 0.05 to 0.2, or 0.05 to 0.15, or 0.05 to 0.1 in weight percent of the total amount of citric acid based on the total weight of the composition. In one subclass of this class, the stabilizer further comprises a second stabilizer component that comprises one or more primary antioxidants and citric acid in the amounts discussed herein. In one subclass of this class, the stabilizer comprises less than 0.1 wt % or no primary antioxidants, based on the total weight of the composition. In one subclass of this class, the stabilizer comprises less than 0.05 wt % or no primary antioxidants, based on the total weight of the composition.
In embodiments, depending on the application, e.g., single use food contact applications, the cellulose acetate composition can include at least one odor modifying additive. In embodiments, depending on the application and components used in the cellulose acetate composition, suitable odor modifying additives can be chosen from: vanillin, Pennyroyal M-1178, almond, cinnamyl, spices, spice extracts, volatile organic compounds or small molecules, and Plastidor. In one embodiment, the odor modifying additive can be vanillin. In embodiments, the cellulose acetate composition can include an odor modifying additive in an amount from 0.01 to 1 wt %, or 0.1 to 0.5 wt %, or 0.1 to 0.25 wt %, or 0.1 to 0.2 wt %, based on the total weight of the composition. Mechanisms for the odor modifying additives can include masking, capturing, complementing or combinations of these.
As discussed above, the cellulose acetate composition can include other additives. In embodiments, the cellulose acetate composition can include at least one compatibilizer. In embodiments, the compatibilizer can be either a non-reactive compatibilizer or a reactive compatibilizer. The compatibilizer can enhance the ability of the cellulose acetate or another component to reach a desired small particle size to improve the dispersion of the chosen component in the composition. In such embodiments, depending on the desired formulation, the biodegradable cellulose acetate can either be in the continuous or discontinuous phase of the dispersion. In embodiments, the compatibilizers used can improve mechanical and/or physical properties of the compositions by modifying the interfacial interaction/bonding between the biodegradable cellulose acetate and another component, e.g., other biodegradable polymer.
In embodiments, the cellulose acetate composition comprises a compatibilizer in an amount from about 1 to about 40 wt %, or about 1 to about 30 wt %, or about 1 to about 20 wt %, or about 1 to about 10 wt %, or about 5 to about 20 wt %, or about 5 to about 10 wt %, or about 10 to about 30 wt %, or about 10 to about 20 wt %, based on the weight of the cellulose acetate composition.
In embodiments, if desired, the cellulose acetate composition can include biodegradation and/or decomposition agents, e.g., hydrolysis assistant or any intentional degradation promoter additives can be added to or contained in the cellulose acetate composition, added either during manufacture of the biodegradable cellulose acetate (BCA) or subsequent to its manufacture and melt or solvent blended together with the BCA to make the cellulose acetate composition. In embodiments, additives can promote hydrolysis by releasing acidic or basic residues, and/or accelerate photo (UV) or oxidative degradation and/or promote the growth of selective microbial colony to aid the disintegration and biodegradation in compost and soil medium. In addition to promoting the degradation, these additives can have an additional function such as improving the processability of the article or improving desired mechanical properties.
One set of examples of possible decomposition agents include inorganic carbonate, synthetic carbonate, nepheline syenite, talc, magnesium hydroxide, aluminum hydroxide, diatomaceous earth, natural or synthetic silica, calcined clay, and the like. In embodiments, it may be desirable that these additives are dispersed well in the cellulose acetate composition matrix. The additives can be used singly, or in a combination of two or more.
Another set of examples of possible decomposition agents are aromatic ketones used as an oxidative decomposition agent, including benzophenone, anthraquinone, anthrone, acetylbenzophenone, 4-octylbenzophenone, and the like. These aromatic ketones may be used singly, or in a combination of two or more.
Other examples include transition metal compounds used as oxidative decomposition agents, such as salts of cobalt or magnesium, e.g., aliphatic carboxylic acid (C12 to C20) salts of cobalt or magnesium, or cobalt stearate, cobalt oleate, magnesium stearate, and magnesium oleate; or anatase-form titanium dioxide, or titanium dioxide may be used. Mixed phase titanium dioxide particles may be used in which both rutile and anatase crystalline structures are present in the same particle. The particles of photoactive agent can have a relatively high surface area, for example from about 10 to about 300 sq. m/g, or from 20 to 200 sq. m/g, as measured by the BET surface area method. The photoactive agent can be added to the plasticizer if desired. These transition metal compounds can be used singly, or in a combination of two or more.
Examples of rare earth compounds that can used as oxidative decomposition agents include rare earths belonging to periodic table Group 3A, and oxides thereof. Specific examples thereof include cerium (Ce), yttrium (Y), neodymium (Nd), rare earth oxides, hydroxides, rare earth sulfates, rare earth nitrates, rare earth acetates, rare earth chlorides, rare earth carboxylates, and the like. More specific examples thereof include cerium oxide, ceric sulfate, ceric ammonium Sulfate, ceric ammonium nitrate, cerium acetate, lanthanum nitrate, cerium chloride, cerium nitrate, cerium hydroxide, cerium octylate, lanthanum oxide, yttrium oxide, Scandium oxide, and the like. These rare earth compounds may be used singly, or in a combination of two or more.
In one embodiment, the BCA composition includes an additive with pro-degradant functionality to enhance biodegradability that comprises a transition metal salt or chemical catalyst, containing transition metals such as cobalt, manganese and iron. The transition metal salt can comprise of tartrate, sterate, oleate, citrate and chloride. The additive can further comprise of a free radical scavenging system and one or more inorganic or organic fillers such as chalk, talc, silica, wollastonite, starch, cotton, reclaimed cardboard and plant matter. The additive can also comprise an enzyme, a bacterial culture, a swelling agent, CMC, sugar or other energy sources. The additive can also comprise hydroxylamine esters and thio compounds.
In certain embodiments, other possible biodegradation and/or decomposition agents can include swelling agents and disintegrants. Swelling agents can be hydrophilic materials that increase in volume after absorbing water and exert pressure on the surrounding matrix. Disintegrants can be additives that promote the breakup of a matrix into smaller fragments in an aqueous environment. Examples include minerals and polymers, including crosslinked or modified polymers and swellable hydrogels. In embodiments, the BCA composition may include water-swellable minerals or clays and their salts, such as laponite and bentonite; hydrophilic polymers, such as poly(acrylic acid) and salts, poly(acrylamide), poly(ethylene glycol) and poly(vinyl alcohol); polysaccharides and gums, such as starch, alginate, pectin, chitosan, psyllium, xanthan gum; guar gum, locust bean gum; and modified polymers, such as crosslinked PVP, sodium starch glycolate, carboxymethyl cellulose, gelatinized starch, croscarmellose sodium; or combinations of these additives.
In embodiments, the BCA composition can comprise a basic additive that can increase decomposition or degradation of the composition or article made from (or comprising) the composition. Examples of basic additives that may be used as oxidative decomposition agents include alkaline earth metal oxides, alkaline earth metal hydroxides, alkaline earth metal carbonates, alkali metal carbonates, alkali metal bicarbonates, ZnO and basic Al2O3. In embodiments, at least one basic additive can be MgO, Mg(OH)2, MgCO3, CaO, Ca(OH)2, CaCO3, NaHCO3, Na2CO3, K2CO3, ZnO KHCO3 or basic Al2O3. In one aspect, alkaline earth metal oxides, ZnO and basic Al2O3 can be used as a basic additive. In embodiments, combinations of different basic additives, or basic additives with other additives, can be used. In embodiments, the basic additive has a pH in the range from greater than 7.0 to 10.0, or 7.1 to 9.5, or 7.1 to 9.0, or 7.1 to 8.5, or 7.1 to 8.0, measured in a 1 wt % mixture/solution of water.
Examples of organic acid additives that can be used as oxidative decomposition agents include acetic acid, propionic acid, butyric acid, valeric acid, citric acid, tartaric acid, oxalic acid, malic acid, benzoic acid, formate, acetate, propionate, butyrate, valerate citrate, tartarate, oxalate, malate, maleic acid, maleate, phthalic acid, phthalate, benzoate, and combinations thereof.
Examples of other hydrophilic polymers or biodegradation promoters may include glycols, polyglycols, polyethers, and polyalcohols or other biodegradable polymers such as poly(glycolic acid), poly(lactic acid), polyethylene glycol, polypropylene glycol, polydioxanes, polyoxalates, poly(α-esters), polycarbonates, polyanhydrides, polyacetals, polycaprolactones, poly(orthoesters), polyamino acids, aliphatic polyesters such as poly(butylene)succinate, poly(ethylene)succinate, starch, regenerated cellulose, or aliphatic-aromatic polyesters such as PBAT.
In embodiments, examples of colorants can include carbon black, iron oxides such as red or blue iron oxides, titanium dioxide, silicon dioxide, cadmium red, calcium carbonate, kaolin clay, aluminum hydroxide, barium sulfate, zinc oxide, aluminum oxide; and organic pigments such as azo and diazo and triazo pigments, condensed azo, azo lakes, naphthol pigments, anthrapyrimidine, benzimidazolone, carbazole, diketopyrrolopyrrole, flavanthrone, indigoid pigments, isoindolinone, isoindoline, isoviolanthrone, metal complex pigments, oxazine, perylene, perinone, pyranthrone, pyrazoloquinazolone, quinophthalone, triarylcarbonium pigments, triphendioxazine, xanthene, thioindigo, indanthrone, isoindanthrone, anthanthrone, anthraquinone, isodibenzanthrone, triphendioxazine, quinacridone and phthalocyanine series, especially copper phthalocyanme and its nuclear halogenated derivatives, and also lakes of acid, basic and mordant dyes, and isoindolinone pigments, as well as plant and vegetable dyes, and any other available colorant or dye.
In embodiments, luster control agents for adjusting the glossiness and fillers can include silica, talc, clay, barium sulfate, barium carbonate, calcium sulfate, calcium carbonate, magnesium carbonate, and the like.
Suitable flame retardants can include silica, metal oxides, phosphates, catechol phosphates, resorcinol phosphates, borates, inorganic hydrates, and aromatic polyhalides.
Antifungal and/or antibacterial agents include polyene antifungals (e.g., natamycin, rimocidin, filipin, nystatin, amphotericin B, candicin, and hamycin), imidazole antifungals such as miconazole (available as MICATIN® from WellSpring Pharmaceutical Corporation), ketoconazole (commercially available as NIZORAL® from McNeil consumer Healthcare), clotrimazole (commercially available as LOTRAMIN® and LOTRAMIN AF® available from Merck and CANESTEN® available from Bayer), econazole, omoconazole, bifonazole, butoconazole, fenticonazole, isoconazole, oxiconazole, sertaconazole (commercially available as ERTACZOO from OrthoDematologics), sulconazole, and tioconazole; triazole antifungals such as fluconazole, itraconazole, isavuconazole, ravuconazole, posaconazole, voriconazole, terconazole, and albaconazole), thiazole antifungals (e.g., abafungin), allylamine antifungals (e.g., terbinafine (commercially available as LAMISIL® from Novartis Consumer Health, Inc.), naftifine (commercially available as NAFTIN® available from Merz Pharmaceuticals), and butenafine (commercially available as LOTRAMIN ULTRA@ from Merck), echinocandin antifungals (e.g., anidulafungin, caspofungin, and micafungin), polygodial, benzoic acid, ciclopirox, tolnaftate (e.g., commercially available as TINACTIN® from MDS Consumer Care, Inc.), undecylenic acid, flucytosine, 5-fluorocytosine, griseofulvin, haloprogin, caprylic acid, and any combination thereof.
Viscosity modifiers having the purpose of modifying the melt flow index or viscosity of the biodegradable cellulose acetate composition that can be used include polyethylene glycols and polypropylene glycols, and glycerin.
In embodiments, other components that can be included in the BCA composition may function as release agents or lubricants (e.g. fatty acids, ethylene glycol distearate), anti-block or slip agents (e.g. fatty acid esters, metal stearate salts (for example, zinc stearate), and waxes), antifogging agents (e.g. surfactants), thermal stabilizers (e.g. epoxy stabilizers, derivatives of epoxidized soybean oil (ESBO), linseed oil, and sunflower oil), anti-static agents, foaming agents, biocides, impact modifiers, or reinforcing fibers. More than one component may be present in the BCA composition. It should be noted that an additional component may serve more than one function in the BCA composition. The different (or specific) functionality of any particular additive (or component) to the BCA composition can be dependent on its physical properties (e.g., molecular weight, solubility, melt temperature, Tg, etc.) and/or the amount of such additive/component in the overall composition. For example, polyethylene glycol can function as a plasticizer at one molecular weight or as a hydrophilic agent (with little or no plasticizing effect) at another molecular weight.
In embodiments, fragrances can be added if desired. Examples of fragrances can include spices, spice extracts, herb extracts, essential oils, smelling salts, volatile organic compounds, volatile small molecules, methyl formate, methyl acetate, methyl butyrate, ethyl acetate, ethyl butyrate, isoamyl acetate, pentyl butyrate, pentyl pentanoate, octyl acetate, myrcene, geraniol, nerol, citral, citronellal, citronellol, linalool, nerolidol, limonene, camphor, terpineol, alpha-ionone, thujone, benzaldehyde, eugenol, isoeugenol, cinnamaldehyde, ethyl maltol, vanilla, vanillin, cinnamyl alcohol, anisole, anethole, estragole, thymol, furaneol, methanol, rosemary, lavender, citrus, freesia, apricot blossoms, greens, peach, jasmine, rosewood, pine, thyme, oakmoss, musk, vetiver, myrrh, blackcurrant, bergamot, grapefruit, acacia, passiflora, sandalwood, tonka bean, mandarin, neroli, violet leaves, gardenia, red fruits, ylang-ylang, acacia farnesiana, mimosa, tonka bean, woods, ambergris, daffodil, hyacinth, narcissus, black currant bud, iris, raspberry, lily of the valley, sandalwood, vetiver, cedarwood, neroli, strawberry, carnation, oregano, honey, civet, heliotrope, caramel, coumarin, patchouli, dewberry, helonial, coriander, pimento berry, labdanum, cassie, aldehydes, orchid, amber, orris, tuberose, palmarosa, cinnamon, nutmeg, moss, styrax, pineapple, foxglove, tulip, wisteria, clematis, ambergris, gums, resins, civet, plum, castoreum, civet, myrrh, geranium, rose violet, jonquil, spicy carnation, galbanum, petitgrain, iris, honeysuckle, pepper, raspberry, benzoin, mango, coconut, hesperides, castoreum, osmanthus, mousse de chene, nectarine, mint, anise, cinnamon, orris, apricot, plumeria, marigold, rose otto, narcissus, tolu balsam, frankincense, amber, orange blossom, bourbon vetiver, opopanax, white musk, papaya, sugar candy, jackfruit, honeydew, lotus blossom, muguet, mulberry, absinthe, ginger, juniper berries, spicebush, peony, violet, lemon, lime, hibiscus, white rum, basil, lavender, balsamics, fo-ti-tieng, osmanthus, karo karunde, white orchid, calla lilies, white rose, rhubrum lily, tagetes, ambergris, ivy, grass, seringa, spearmint, clary sage, cottonwood, grapes, brimbelle, lotus, cyclamen, orchid, glycine, tiare flower, ginger lily, green osmanthus, passion flower, blue rose, bay rum, cassie, African tagetes, Anatolian rose, Auvergne narcissus, British broom, British broom chocolate, Bulgarian rose, Chinese patchouli, Chinese gardenia, Calabrian mandarin, Comoros Island tuberose, Ceylonese cardamom, Caribbean passion fruit, Damascena rose, Georgia peach, white Madonna lily, Egyptian jasmine, Egyptian marigold, Ethiopian civet, Farnesian cassie, Florentine iris, French jasmine, French jonquil, French hyacinth, Guinea oranges, Guyana wacapua, Grasse petitgrain, Grasse rose, Grasse tuberose, Haitian vetiver, Hawaiian pineapple, Israeli basil, Indian sandalwood, Indian Ocean vanilla, Italian bergamot, Italian iris, Jamaican pepper, May rose, Madagascar ylang-ylang, Madagascar vanilla, Moroccan jasmine, Moroccan rose, Moroccan oakmoss, Moroccan orange blossom, Mysore sandalwood, Oriental rose, Russian leather, Russian coriander, Sicilian mandarin, South African marigold, South American tonka bean, Singapore patchouli, Spanish orange blossom, Sicilian lime, Reunion Island vetiver, Turkish rose, Thai benzoin, Tunisian orange blossom, Yugoslavian oakmoss, Virginian cedarwood, Utah yarrow, West Indian rosewood, and the like, and any combination thereof.
An important general feature of the melt-processable compositions and melts of the present invention is the unexpected stability and retention of key attributes through melting and melt processing into melt-formed articles. Parameters that can demonstrate this feature include (but are not limited to) melt stability (as demonstrated and quantified for example by one or both of viscosity change or molecular weight change) and color change (also referred to herein and quantified as Ab*). In measuring and evaluating each of these parameters, an initial measurement of a given sample parameter is taken and compared to a second measurement of that parameter after the sample has been melted and cooled. For example, in measuring color change Ab*, a sample is processed through at least one temperature and time “cycle” selected to represent a suitable melt temperature for a given composition and a typical cycle time for a given type of melt processing used to manufacture melt-formed articles. In one non-limiting example, cycle times for testing a composition for use in injection molding processes might use a “regular” cycle time of ˜39 seconds or a “doubled” cycle time of about 78 seconds. Samples tested may be formed from a composition is its entirety or may be combinations of key composition components (such as for example a biodegradable melt-stable cellulose acetate plus a plasticizer) to better isolate the variables present in interpreting the results. Non-limiting details for testing protocols are set forth in the examples herein.
An important feature of the melt-processable, biodegradable, cellulose acetate composition of the present invention is its ability to retain desirable levels of properties such as molecular weight, viscosity and color, or minimize change thereto, during melt processing. Accordingly, in one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention may be characterized by a plasticized cellulose acetate percent molecular weight change (or ΔW) of no more than 10% or no more than 9% or no more than 8% or no more than 7% wherein ΔW is the absolute value of the calculation
with W1 being a first molecular weight (Mn) prior to a specified melt processing treatment and W2 being the molecular weight (Mn) after the specified melt processing treatment. In one non-limiting example used to generate data set forth herein, a plasticized cellulose acetate sample (which includes the cellulose acetate plus the plasticizer and acid scavenger in their relative amounts present in the final composition) is compared before and after a melt processing treatment that includes generating a melt and maintaining the melt at 240 C for 20 min. (hereinafter referred to as the Specified ΔW Melt Processing Treatment).
In one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention may be characterized by a plasticized cellulose acetate percent viscosity change (or ΔV) of no more than 20% or no more than 15% or no more than 10% or no more than 5% wherein ΔV is the absolute value of the calculation
with V1 being a first viscosity prior to a specified melt processing treatment and V2 being a second viscosity after a specified melt processing treatment. In one non-limiting example used to generate data set forth herein, a plasticized cellulose acetate sample (which includes the cellulose acetate plus the plasticizer and acid scavenger in their relative amounts present in the final composition) is compared before and after a melt processing treatment that includes processing in a rheometer (TA instruments Ares Melt Rheometer) at 220° C. for 20 minutes at 25 rad/sec. under N2, with V1 measured at a time of t=0 and V2 measured at a time of 20 min.
In one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention may also be described using other characterizations or parameters. In one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention may be characterized by a color value (b*) of less than 40, or less than 35, or less than 30, or less than 25, or less than 20, or less than 10 (measured on a molded article such as a film, plaque or disc). The parameter b* is a known component of the CIE L*a*b* color measurement technique as described for example in ASTM D 6290-98 and ASTM E308-99. Low color values and color stability are often desirable by manufacturers and purchasers of melt-formed articles. In one or more embodiments, biodegradable melt-stable cellulose acetates of the present invention may be characterized by a color value (b*) of less than 40, or less than 35, or less than 30, or less than 25, or less than 20, or less than 10.
In one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention may be characterized by a plasticized cellulose acetate color change (Δb*) of no more than 8 or no more than 7 or no more than 6 or no more than 5 or no more than 4, wherein Δb* is the absolute value of the calculation.
with b*1 being a first b* value measured prior to a specified melt processing treatment and b*2 is a second b* value measured after the specified melt processing treatment. In one non-limiting example used to generate data set forth herein, a plasticized cellulose acetate sample is processed to make a plaque with a “regular” cycle time with b*1 and compared to a plaque with a cycle time that is double the “regular” cycle time with b*2 as described herein (hereinafter the Specified Δb* Melt Processing Treatment).
In one or more embodiments, the melt-processable, biodegradable, cellulose acetate composition of the present invention may be characterized by a spiral flow length of at least 4.25 inches 10.8 cm at a barrel temp of 227 C or at least 12.2 cm at a barrel temp of 238 C or at least 12.7 cm at a barrel temperature of 249 C cm, when the composition is molded with a spiral flow mold with the conditions of the indicated barrel temperature, a molding pressure of 13.8 MPa, a mold thickness of 0.8 mm, and a mold width of 12.7 mm. The details regarding the Spiral Flow testing are set forth below.
A reciprocating screw injection molding machine having 110 tons of clamping force with a screw diameter of 32 mm was equipped with a water-cooled, cold runner mold with a spiral-shaped cavity having dimensions of 12.7 mm wide×0.8 mm deep×1524 mm in length. The cavity was fed via a 8.9 cm long cold sprue with a nominal 1.0 cm diameter and 3-degree taper, followed by a 2.5 cm long cold runner with 0.8 cm nominal diameter, followed by a rectangular gate 0.6 cm wide×0.1 cm thick×0.3 gm long. Variables controlled for the range of experimentation included resin drying, injection unit barrel temperature, mold temperature, initial injection speed, injection pressure limit, screw rotation speed and back pressure on screw recovery, injection time, and cycle time.
For each combination of variables, responses included distance of melt travel in the spiral-shaped cavity, excluding the runner and gate. The injection process was allowed to stabilize at each set of conditions—typically 10 to 15 shots—and then 10 molded specimens were collected for an average reported flow length.
All materials were molded using pressure control, with mold temperature of 63 C, initial injection speed of 1 in/s, injection unit pressure limit of 13.8 MPa, injection time of 10 s, cycle time of 38 s, maximum cushion of 0.1 screw recovery rotation speed of 150 rpm, and screw recovery back pressure of 100 psi.
As described herein, the composition of the present invention is melt-processable and may be useful in forming melt-formed articles. Accordingly, in another aspect, the present invention is directed to a melt-processable, biodegradable cellulose acetate melt. The term “melt” is utilized to generally describe a flowable, liquid form of the composition, sometimes viscous in nature, typically created by raising the composition to a temperature at or slightly above its components' melt temperatures (in contrast for example to addition of a solvent to form a dispersion, suspension or solution). A melt is typically the form necessary for melt-processing to produce a melt-formed article.
In embodiments, the cellulose acetate composition is melt-processable and can be converted into a melt and formed into useful melt-formed articles. Accordingly, in another aspect, the present invention is a melt-formed biodegradable article. The melt-formed biodegradable article of the present invention includes or is formed from the melt-processable, biodegradable cellulose acetate composition of the present invention described herein. As the melt-formed biodegradable article is typically formed from a composition in melt or molten form, the melt-formed biodegradable article may alternatively be describes as including or formed from the melt-processable, biodegradable cellulose acetate melt of the present invention. The phrase “melt-formed” is meant to generally include all useful articles formable by melt forming processes. Non-limiting examples of melt forming processes include injection molding, blow molding, extrusion, profiling, thermoforming, foaming, casting, 3D printing (or additive manufacturing) and the like. Accordingly, melt-formed articles of the present invention may include (but are not limited to) extruded articles, thermoformed articles, injection molded articles, blow molded articles, profiled articles, foams and foam articles, thermoformed articles, cast articles, 3D printed articles and the like. Specific article forms may include films, sheets, fibers, profile extruded articles such as drinking straws, expanded or extruded foams and related foam objects and the like. Melt-formed articles is also intended to include articles with one or more melt-formed components such as multilayer laminates with one or more melt-formed layers,
In one or more embodiments, the melt-formed articles of the present invention may be molded single use food contact articles, including articles that are biodegradable and/or compostable (i.e., either pass industrial or home compostability tests/criterial as discussed herein). In embodiments, the cellulose acetate compositions can be extrudable, moldable, castable, thermoformable, or can be 3-D printed. In embodiments, the articles are environmentally non-persistent. “Environmentally non-persistent” is meant to describe materials or articles that, upon reaching an advanced level of disintegration, become amenable to total consumption by the natural microbial population. The degradation of biodegradable cellulose acetate ultimately leads its conversion to carbon dioxide, water and biomass.
In embodiments, articles comprising the cellulose acetate compositions (discussed herein) are provided that have a maximum thickness up to 150 mils, or 140 mils, or 130 mils, or 120 mils, or 110 mils, or 100 mils, or 90 mils, or 80 mils, or 70 mils, or 60 mils, or 50 mils, or 40 mils, or 30 mils, or 25 mils, or 20 mils, or 15 mils, or 10 mils, and are biodegradable and compostable. In embodiments, articles comprising the cellulose acetate compositions (discussed herein) are provided that have a maximum thickness up to 150 mils, or 140 mils, or 130 mils, or 120 mils, or 110 mils, to 100 mils, or 90 mils, or 80 mils, or 70 mils, or 60 mils, or 50 mils, or 40 mils, or 30 mils, or 25 mils, or 20 mils, or 15 mils, or 10 mils, and are environmentally non-persistent.
In embodiments, the melt-processable biodegradable cellulose acetate composition of the present invention, as well as the melt and the melt-formed article, includes recycle content. In one or more embodiments, the recycle content includes biodegradable cellulose acetate regrind. The term “regrind” is intended to include material sourced from reclaimed, scrap, in-house scrap such as scrap from molders, off-spec or post-industrial sources that has been ground, milled, crushed, pulverized or the like to a particle- or powder-like form.
In one or more embodiments, the recycle content is provided by a reactant derived from recycled material that is the source of one or more acetyl groups on the BCA. In embodiments, the reactant is derived from recycled plastic. In embodiments, the reactant is derived from recycled plastic content syngas. By “recycled plastic content syngas” is meant syngas obtained from a synthesis gas operation utilizing a feedstock that contains at least some content of recycled plastics, as described in the various embodiments more fully herein below. In embodiments, the recycled plastic content syngas can be made in accordance with any of the processes for producing syngas described herein; can comprise, or consist of, any of the syngas compositions or syngas composition streams described herein; or can be made from any of the feedstock compositions described herein.
In embodiments, the feedstock (for the synthesis gas operation) can be in the form of a combination of one or more particulated fossil fuel sources and particulated recycled plastics. In one embodiment or in any of the mentioned embodiments, the solid fossil fuel source can include coal. In embodiments, the feedstock is fed to a gasifier along with an oxidizer gas, and the feedstock is converted to syngas.
In embodiments, the recycled plastic content syngas is utilized to make at least one chemical intermediate in a reaction scheme to make a Recycle BCA. In embodiments, the recycled plastic content syngas can be a component of feedstock (used to make at least one cellulose acetate (referred to herein from time to CA) intermediate that includes other sources of syngas, hydrogen, carbon monoxide, or combinations thereof. In one embodiment or in any of the mentioned embodiments, the only source of syngas used to make the CA intermediates is the recycled plastic content syngas.
In embodiments, the CA intermediates made using the recycled content syngas, e.g., recycled plastic content syngas, can be chosen from methanol, acetic acid, methyl acetate, acetic anhydride and combinations thereof. In embodiments, the CA intermediates can be a at least one reactant or at least one product in one or more of the following reactions: (1) syngas conversion to methanol; (2) syngas conversion to acetic acid; (3) methanol conversion to acetic acid, e.g., carbonylation of methanol to produce acetic acid; (4) producing methyl acetate from methanol and acetic acid; and (5) conversion of methyl acetate to acetic anhydride, e.g., carbonylation of methyl acetate and methanol to acetic acid and acetic anhydride.
In embodiments, recycled plastic content syngas is used to produce at least one cellulose reactant. In embodiments, the recycled plastic content syngas is used to produce at least one Recycle BCA.
In embodiments, the recycled plastic content syngas is utilized to make acetic anhydride. In embodiments, syngas that comprises recycled plastic content syngas is first converted to methanol and this methanol is then used in a reaction scheme to make acetic anhydride. “RPS acetic anhydride” refers to acetic anhydride that is derived from recycled plastic content syngas. Derived from means that at least some of the feedstock source material (that is used in any reaction scheme to make a CA intermediate) has some content of recycled plastic content syngas.
In embodiments, the RPS acetic anhydride is utilized as a CA intermediate reactant for the esterification of cellulose to prepare a Recycle BCA, as discussed more fully above. In embodiments, the RPS acetic acid is utilized as a reactant to prepare cellulose acetate or cellulose diacetate.
In embodiments, the Recycle CA is prepared from a cellulose reactant that comprises acetic anhydride that is derived from recycled plastic content syngas.
In embodiments, the recycled plastic content syngas comprises gasification products from a gasification feedstock. In an embodiment, the gasification products are produced by a gasification process using a gasification feedstock that comprises recycled plastics. In embodiments, the gasification feedstock comprises coal.
In embodiments, the gasification feedstock comprises a liquid slurry that comprises coal and recycled plastics. In embodiments, the gasification process comprises gasifying said gasification feedstock in the presence of oxygen.
In one aspect, a Recycle BCA composition is provided that comprises at least one biodegradable cellulose ester having at least one substituent on an anhydroglucose unit (AGU) derived from one or more chemical intermediates, at least one of which is obtained at least in part from recycled plastic content syngas.
In embodiments, the Recycle BCA is biodegradable and contains content derived from a renewable source, e.g., cellulose from wood or cotton linter, and content derived from a recycled material source, e.g., recycled plastics. Thus, in embodiments, a melt processible material is provided that is biodegradable and contains both renewable and recycled content, i.e., made from renewable and recycled sources.
The biodegradable cellulose acetate useful in embodiments of the present invention can have a degree of substitution in the range of from 1.0 to 2.5. In some cases, the cellulose acetate as described herein may have an average degree of substitution of at least about 1.0, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45 or 1.5 and/or not more than about 2.5, 2.45, 2.4, 2.35, 2.3, 2.25, 2.2, 2.15, 2.1, 2.05, 2.0, 1.95, 1.9, 1.85, 1.8 or 1.75.
In embodiments, the biodegradable cellulose acetate may have a number average molecular weight (Mn) of not more than 100,000, or not more than 90,000, measured using gel permeation chromatography with a polystyrene equivalent and using N-methyl-2-pyrrolidone (NMP) as the solvent. In some cases, the biodegradable cellulose acetate may have a Mn of at least about 10,000, at least about 20,000, 25,000, 30,000, 35,000, 40,000, or 45,000 and/or not more than about 100,000, 95,000, 90,000, 85,000, 80,000, 75,000, 70,000, 65,000, 60,000, or 50,000.
In embodiments, the BCA containing article can be biodegradable and have a certain degree of degradation. The degree of degradation can be characterized by the weight loss of a sample over a given period of exposure to certain environmental conditions. In some cases, the BCA composition can exhibit a weight loss of at least about 5, 10, 15, or 20 percent after burial in soil for 60 days and/or a weight loss of at least about 15, 20, 25, 30, or 35 percent after 15 days of exposure to a typical municipal composter. However, the rate of degradation may vary depending on the particular end use. Exemplary test conditions are provided in U.S. Pat. Nos. 5,970,988 and 6,571,802.
In some embodiments, the BCA composition may be in the form of biodegradable single use (formed/molded) articles. It has been found that melt-processable BCA compositions as described herein can exhibit enhanced levels of environmental non-persistence, characterized by better-than-expected degradation under various environmental conditions. Melt-formed BCA containing articles described herein may meet or exceed passing standards set by international test methods and authorities for industrial compostability, home compostability, and/or soil biodegradability.
To be considered “compostable,” a material must meet the following four criteria: (1) the material should pass biodegradation requirement in a test under controlled composting conditions at elevated temperature (58° C.) according to ISO 14855-1 (2012) which correspond to an absolute 90% biodegradation or a relative 90% to a control polymer, (2) the material tested under aerobic composting condition according to ISO16929 (2013) must reach a 90% disintegration; (3) the test material must fulfill all the requirements on volatile solids, heavy metals and fluorine as stipulated by ASTM D6400 (2012), EN 13432 (2000) and ISO 17088 (2012); and (4) the material should not cause negative on plant growth. As used herein, the term “biodegradable” generally refers to the biological conversion and consumption of organic molecules. Biodegradability is an intrinsic property of the material itself, and the material can exhibit different degrees of biodegradability, depending on the specific conditions to which it is exposed. The term “disintegrable” refers to the tendency of a material to physically decompose into smaller fragments when exposed to certain conditions. Disintegration depends both on the material itself, as well as the physical size and configuration of the article being tested. Ecotoxicity measures the impact of the material on plant life, and the heavy metal content of the material is determined according to the procedures laid out in the standard test method.
The CA composition (or article comprising same) can exhibit a biodegradation of at least 70 percent in a period of not more than 50 days, when tested under aerobic composting conditions at ambient temperature (28° C.±2° C.) according to ISO 14855-1 (2012). In some cases, the CA composition (or article comprising same) can exhibit a biodegradation of at least 70 percent in a period of not more than 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, or 37 days when tested under these conditions, also called “home composting conditions.” These conditions may not be aqueous or anaerobic. In some cases, the CA composition (or article comprising same) can exhibit a total biodegradation of at least about 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, or 88 percent, when tested under according to ISO 14855-1 (2012) for a period of 50 days under home composting conditions. This may represent a relative biodegradation of at least about 95, 97, 99, 100, 101, 102, or 103 percent, when compared to cellulose subjected to identical test conditions.
To be considered “biodegradable,” under home composting conditions according to the French norm NF T 51-800 and the Australian standard AS 5810, a material must exhibit a biodegradation of at least 90 percent in total (e.g., as compared to the initial sample), or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item. The maximum test duration for biodegradation under home compositing conditions is 1 year. The CA composition as described herein may exhibit a biodegradation of at least 90 percent within not more than 1 year, measured according 14855-1 (2012) under home composting conditions. In some cases, the CA composition (or article comprising same) may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 1 year, or CA composition (or article comprising same) may exhibit 100 percent biodegradation within not more than 1 year, measured according 14855-1 (2012) under home composting conditions.
Additionally, or in the alternative, the CA composition (or article comprising same) described herein may exhibit a biodegradation of at least 90 percent within not more than about 350, 325, 300, 275, 250, 225, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, 100, 90, 80, 70, 60, or 50 days, measured according 14855-1 (2012) under home composting conditions. In some cases, the CA composition (or article comprising same) can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 70, 65, 60, or 50 days of testing according to ISO 14855-1 (2012) under home composting conditions. As a result, the CA composition (or article comprising same) may be considered biodegradable according to, for example, French Standard NF T 51-800 and Australian Standard AS 5810 when tested under home composting conditions.
The CA composition (or article comprising same) can exhibit a biodegradation of at least 60 percent in a period of not more than 45 days, when tested under aerobic composting conditions at a temperature of 58° C. (±2° C.) according to ISO 14855-1 (2012). In some cases, the CA composition (or article comprising same) can exhibit a biodegradation of at least 60 percent in a period of not more than 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, or 27 days when tested under these conditions, also called “industrial composting conditions.” These may not be aqueous or anaerobic conditions. In some cases, the CA composition (or article comprising same) can exhibit a total biodegradation of at least about 65, 70, 75, 80, 85, 87, 88, 89, 90, 91, 92, 93, 94, or 95 percent, when tested under according to ISO 14855-1 (2012) for a period of 45 days under industrial composting conditions. This may represent a relative biodegradation of at least about 95, 97, 99, 100, 102, 105, 107, 110, 112, 115, 117, or 119 percent, when compared to the same CA composition (or article comprising same) subjected to identical test conditions.
To be considered “biodegradable,” under industrial composting conditions according to ASTM D6400 and ISO 17088, at least 90 percent of the organic carbon in the whole item (or for each constituent present in an amount of more than 1% by dry mass) must be converted to carbon dioxide by the end of the test period when compared to the control or in absolute. According to European standard ED 13432 (2000), a material must exhibit a biodegradation of at least 90 percent in total, or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item. The maximum test duration for biodegradability under industrial compositing conditions is 180 days. The CA composition (or article comprising same) described herein may exhibit a biodegradation of at least 90 percent within not more than 180 days, measured according 14855-1 (2012) under industrial composting conditions. In some cases, the CA composition (or article comprising same) may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 180 days, or CA composition (or article comprising same) may exhibit 100 percent biodegradation within not more than 180 days, measured according 14855-1 (2012) under industrial composting conditions.
Additionally, or in the alternative, CA composition (or article comprising same) described herein may exhibit a biodegradation of least 90 percent within not more than about 175, 170, 165, 160, 155, 150, 145, 140, 135, 130, 125, 120, 115, 110, 105, 100, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, or 45 days, measured according 14855-1 (2012) under industrial composting conditions. In some cases, the CA composition (or article comprising same) can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 65, 60, 55, 50, or 45 days of testing according to ISO 14855-1 (2012) under industrial composting conditions. As a result, the CA composition (or article comprising same) described herein may be considered biodegradable according to ASTM D6400 and ISO 17088 when tested under industrial composting conditions.
The CA composition (or article comprising same) may exhibit a biodegradation in soil of at least 60 percent within not more than 130 days, measured according to ISO 17556 (2012) under aerobic conditions at ambient temperature. In some cases, CA composition (or article comprising same) can exhibit a biodegradation of at least 60 percent in a period of not more than 130, 120, 110, 100, 90, 80, or 75 days when tested under these conditions, also called “soil composting conditions.” These may not be aqueous or anaerobic conditions. In some cases, the CA composition (or article comprising same) can exhibit a total biodegradation of at least about 65, 70, 72, 75, 77, 80, 82, or 85 percent, when tested under according to ISO 17556 (2012) for a period of 195 days under soil composting conditions. This may represent a relative biodegradation of at least about 70, 75, 80, 85, 90, or 95 percent, when compared to the same CA composition (or article comprising same) subjected to identical test conditions.
In order to be considered “biodegradable,” under soil composting conditions according the OK biodegradable SOIL conformity mark of Vingotte and the DIN Gepruft Biodegradable in soil certification scheme of DIN CERTCO, a material must exhibit a biodegradation of at least 90 percent in total (e.g., as compared to the initial sample), or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item. The maximum test duration for biodegradability under soil compositing conditions is 2 years. The CA composition (or article comprising same) as described herein may exhibit a biodegradation of at least 90 percent within not more than 2 years, 1.75 years, 1 year, 9 months, or 6 months measured according to ISO 17556 (2012) under soil composting conditions. In some cases, the CA composition (or article comprising same) may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 2 years, or CA composition (or article comprising same) may exhibit 100 percent biodegradation within not more than 2 years, measured according to ISO 17556 (2012) under soil composting conditions.
Additionally, or in the alternative, CA composition (or article comprising same) described herein may exhibit a biodegradation of at least 90 percent within not more than about 700, 650, 600, 550, 500, 450, 400, 350, 300, 275, 250, 240, 230, 220, 210, 200, or 195 days, measured according 17556 (2012) under soil composting conditions. In some cases, the CA composition (or article comprising same) can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 225, 220, 215, 210, 205, 200, or 195 days of testing according to ISO 17556 (2012) under soil composting conditions. As a result, the CA composition (or article comprising same) described herein may meet the requirements to receive The OK biodegradable SOIL conformity mark of Vingotte and to meet the standards of the DIN Gepruft Biodegradable in soil certification scheme of DIN CERTCO.
In some embodiments, CA composition (or article comprising same) of the present invention may include less than 1, 0.75, 0.50, or 0.25 weight percent of components of unknown biodegradability. In some cases, the CA composition (or article comprising same) described herein may include no components of unknown biodegradability.
In addition to being biodegradable under industrial and/or home composting conditions, CA composition (or article comprising same) as described herein may also be compostable under home and/or industrial conditions. As described previously, a material is considered compostable if it meets or exceeds the requirements set forth in EN 13432 for biodegradability, ability to disintegrate, heavy metal content, and ecotoxicity. The CA composition (or article comprising same) described herein may exhibit sufficient compostability under home and/or industrial composting conditions to meet the requirements to receive the OK compost and OK compost HOME conformity marks from Vingotte.
In some cases, the CA composition (or article comprising same) described herein may have a volatile solids concentration, heavy metals and fluorine content that fulfill all of the requirements laid out by EN 13432 (2000). Additionally, the CA composition (or article comprising same) may not cause a negative effect on compost quality (including chemical parameters and ecotoxicity tests).
In some cases, the CA composition (or article comprising same) can exhibit a disintegration of at least 90 percent within not more than 26 weeks, measured according to ISO 16929 (2013) under industrial composting conditions. In some cases, the CA composition (or article comprising same) may exhibit a disintegration of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent under industrial composting conditions within not more than 26 weeks, or CA composition (or article comprising same) may be 100 percent disintegrated under industrial composting conditions within not more than 26 weeks. Alternatively, or in addition, the CA composition (or article comprising same) may exhibit a disintegration of at least 90 percent under industrial compositing conditions within not more than about 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, or 10 weeks, measured according to ISO 16929 (2013). In some cases, the CA composition (or article comprising same) described herein may be at least 97, 98, 99, or 99.5 percent disintegrated within not more than 12, 11, 10, 9, or 8 weeks under industrial composting conditions, measured according to ISO 16929 (2013).
In some cases, the CA composition (or article comprising same) can exhibit a disintegration of at least 90 percent within not more than 26 weeks, measured according to ISO 16929 (2013) under home composting conditions. In some cases, the CA composition (or article comprising same) may exhibit a disintegration of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent under home composting conditions within not more than 26 weeks, or the CA composition (or article comprising same) may be 100 percent disintegrated under home composting conditions within not more than 26 weeks.
Alternatively, or in addition, the CA composition may exhibit a disintegration of at least 90 percent within not more than about 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, or 15 weeks under home composting conditions, measured according to ISO 16929 (2013). In some cases, the CA composition (or article comprising same) described herein may be at least 97, 98, 99, or 99.5 percent disintegrated within not more than 20, 19, 18, 17, 16, 15, 14, 13, or 12 weeks, measured under home composting conditions according to ISO 16929 (2013).
In embodiments or in combination with any other embodiments, when the CA composition is formed into a film having a thickness of 0.13, or 0.25. or 0.38, or 0.51, or 0.64, or 0.76, or 0.89, or 1.02, or 1.14, or 1.27, or 1.40, or 1.52 mm, the film exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In certain embodiments, when the CA composition is formed into a film having a thickness of 0.76, or 0.89, or 1.02, or 1.14, or 1.27, or 1.40, or 1.52 mm, the film exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In certain embodiments, when the CA composition is formed into a film having a thickness of 0.13, or 0.25. or 0.38, or 0.51, or 0.64, or 0.76, or 0.89, or 1.02, or 1.14, or 1.27, or 1.40, or 1.52 mm, the film exhibits greater than 90, or 95, or 96, or 97, or 98, or 99% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In certain embodiments, when the CA composition is formed into a film having a thickness of 0.13, or 0.25. or 0.38, or 0.51, or 0.64, or 0.76, or 0.89, or 1.02, or 1.14, or 1.27, or 1.40, or 1.52 mm, the film exhibits greater than 90, or 95, or 96, or 97, or 98, or 99% disintegration after 8, or 9, or 10, or 11, or 12, or 13, or 14, or 15, or 16 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In some embodiments, the CA composition (or article comprising same) described herein may be substantially free of photodegradation agents. For example, the CA composition (or article comprising same) may include not more than about 1, 0.75, 0.50, 0.25, 0.10, 0.05, 0.025, 0.01, 0.005, 0.0025, or 0.001 weight percent of photodegradation agent, based on the total weight of the CA composition (or article comprising same), or the CA composition (or article comprising same) may include no photodegradation agents. Examples of such photodegradation agents include, but are not limited to, pigments which act as photooxidation catalysts and are optionally augmented by the presence of one or more metal salts, oxidizable promoters, and combinations thereof. Pigments can include coated or uncoated anatase or rutile titanium dioxide, which may be present alone or in combination with one or more of the augmenting components such as, for example, various types of metals. Other examples of photodegradation agents include benzoins, benzoin alkyl ethers, benzophenone and its derivatives, acetophenone and its derivatives, quinones, thioxanthones, phthalocyanine and other photosensitizers, ethylene-carbon monoxide copolymer, aromatic ketone-metal salt sensitizers, and combinations thereof.
In an aspect, biodegradable and/or compostable articles are provided that comprise the CA compositions, as described herein. In embodiments, the articles are made from moldable thermoplastic material comprising the CA compositions, as described herein.
In embodiments, the articles are single use food contact articles. Examples of such articles that can be made with the CA compositions include cups, trays, multi-compartment trays, clamshell packaging, candy sticks, films, sheets, trays and lids (e.g., thermoformed), straws, plates, bowls, portion cups, food packaging, liquid carrying containers, solid or gel carrying containers, and cutlery. In embodiments, the articles can be horticultural articles. Examples of such articles that can be made with the CA compositions include plant pots, plant tags, mulch films, and agricultural ground cover. In other embodiments articles made with the CA compositions can be foamed and thermoformed. Examples include foam clamshells, foam plates, foam bowls, foam trays, and foam food packaging trays for proteins like poultry, beef, and fish and foam retail grocery store trays for meats and vegetables.
In another aspect, a CA composition is provided that comprises Recycle BCA prepared by an integrated process which comprises the processing steps of: (1) preparing a recycled plastic content syngas in a synthesis gas operation utilizing a feedstock that contains a solid fossil fuel source and at least some content of recycled plastics; (2) preparing at least one chemical intermediate from said syngas; (3) reacting said chemical intermediate in a reaction scheme to prepare at least one cellulose reactant for preparing a Recycle BCA, and/or selecting said chemical intermediate to be at least one cellulose reactant for preparing a Recycle BCA; and (4) reacting said at least one cellulose reactant to prepare said Recycle BCA; wherein said Recycle BCA comprises at least one substituent on an anhydroglucose unit (AGU) derived from recycled plastic content syngas.
In embodiments, the processing steps (1) to (4) are carried out in a system that is in fluid and/or gaseous communication (i.e., including the possibility of a combination of fluid and gaseous communication). It should be understood that the chemical intermediates, in one or more of the reaction schemes for producing Recycle BCAs starting from recycled plastic content syngas, may be temporarily stored in storage vessels and later reintroduced to the integrated process system.
In embodiments, the at least one chemical intermediate is chosen from methanol, methyl acetate, acetic anhydride, acetic acid, or combinations thereof. In embodiments, one chemical intermediate is methanol, and the methanol is used in a reaction scheme to make a second chemical intermediate that is acetic anhydride. In embodiments, the cellulose reactant is acetic anhydride.
In embodiments, the melt-processable, biodegradable cellulose acetate composition comprises BCA (as described herein), a plasticizer composition and a stabilizer composition, wherein the plasticizer composition comprises one or more food grade plasticizers and is present in an amount from 13 to 26, or 14 to 26, or 15 to 26, or 16 to 26, or 17 to 26, or 13 to 25, or 14 to 25, or 15 to 25, or 16 to 25, or 17 to 25, or 13 to 23, or 14 to 22, or 15 to 23, or 13 to 20, or 14 to 20, or 15 to 20, or 16 to 20, or 17 to 20, or 13 to 17, or 14 to 17, or 15 to 17, or 13 to less than 17, or 14 to less than 17, or 15 to less than 17 wt %, based on the total weight of the cellulose ester composition; and wherein the stabilizer composition comprises one or more secondary antioxidants and is present in an amount from 0.08 to 0.8, or 0.08 to 0.7, or 0.08 to 0.6 wt %, based on the total weight of the cellulose ester composition. In certain embodiments, the plasticizer is present in an amount from 10 to 50, or 10 to 45, or 10 to 40, or 10 to 35, or 10 to 30 wt %.
In embodiments, the plasticizer composition comprises triacetin in an amount from 10 to 35, or 10 to 30, or 10 to 26, or 10 to 25, or 10 to 23, or 10 to 20, or 10 to 17, or 10 to 15, or 10 to 14, or 10 to 13, or 10 to 12, or 11 to 35, or 11 to 30, or 11 to 26, or 11 to 25, or 11 to 23, or 11 to 20, or 11 to 17, or 11 to 15, or 11 to 14, or 11 to 13, or 12 to 35, or 12 to 30, or 12 to 26, or 12 to 25, or 12 to 23, or 12 to 20, or 12 to 17, or 12 to 15, or 12 to 14, or 13 to 35, or 13 to 30, or 13 to 26, or 13 to 25, or 13 to 23, or 13 to 20, or 13 to 17, or 13 to 15, or 14 to 35, or 14 to 30, or 14 to 26, or 14 to 25, or 14 to 23, or 14 to 20, or 14 to 17, or 14 to 16, or 15 to 35, or 15 to 30, or 15 to 26, or 15 to 25, or 15 to 23, or 15 to 20, or 15 to 17, or 16 to 35, or 16 to 30, or 16 to 26, or 16 to 25, or 16 to 23, or 16 to 20, or 16 to 18, or 17 to 35, or 17 to 30, or 17 to 26, or 17 to 25, or 17 to 23, or 17 to 20, or 17 to 19, or 18 to 35, or 18 to 30, or 18 to 26, or 18 to 25, or 18 to 23, or 18 to 20, or 19 to 35, or 19 to 30, or 19 to 26, or 19 to 25, or 19 to 23, or 19 to 21, or 20 to 35, or 20 to 30, or 20 to 26, or 20 to 25, or 20 to 23, or 20 to 22, or 21 to 35, or 21 to 30, or 21 to 26, or 21 to 25, or 21 to 23, or 21 to 23, or 22 to 35, or 22 to 30, or 22 to 26, or 22 to 25, or 22 to 24, or 23 to 35, or 23 to 30, or 23 to 26, or 23 to 25, or 24 to 35, or 24 to 30, or 24 to 26, or 25 to 35, or 25 to 30, or 25 to 27 wt %, based on the total weight of the cellulose ester composition.
In certain embodiments, the plasticizer composition comprises triacetin in an amount from 15 to 20, or 16 to 19 wt %, based on the total weight of the cellulose ester composition; and the stabilizer composition comprises one or more secondary antioxidants in an amount from 0.05 to 0.6, or 0.05 to 0.55, or 0.05 to 0.5, or 0.05 to 0.4, or 0.05 to 0.3, or 0.07 to 0.6, or 0.07 to 0.55, or 0.07 to 0.5, or 0.07 to 0.4, or 0.07 to 0.3, or 0.08 to 0.6, or 0.08 to 0.55, or 0.08 to 0.5, or 0.08 to 0.4, or 0.08 to 0.3, or 0.1 to 0.6, or 0.1 to 0.55, or 0.1 to 0.5, or 0.1 to 0.4, or 0.1 to 0.3, or 0.15 to 0.6, or 0.15 to 0.55, or 0.15 to 0.5, or 0.15 to 0.4, or 0.15 to 0.3, or 0.2 to 0.6, or 0.2 to 0.55, or 0.2 to 0.5, or 0.2 to 0.4 wt % and one or more primary antioxidants in an amount from 0.1 to 0.5, or 0.1 to 0.4, or 0.2 to 0.4 wt %, where wt % is based on the total weight of the cellulose ester composition. In one class of this embodiment, the one or more secondary antioxidants comprises a phosphite compound (e.g., Weston 705T or Doverphos S-9228T), DLTDP or a combination thereof and the one or more primary antioxidants comprises Irganox 1010, BHT or a combination thereof. In embodiments, the cellulose ester composition has a b* less than 40, or less than 35, or less than 30, or less than 25, or less than 20, or less than 15 after normal cycle time during injection molding (as described in the examples); or has a b* less than 40, or less than 35, or less than 30, or less than 25, or less than 20 after doubling the cycle time during injection molding (as described in the examples).
In embodiments, the plasticizer composition comprises polyethylene glycol having an average molecular weight of from 200 to 10,000, or 200 to 8,000, or 200 to 6,000, or 200 to 5,000, or 200 to 4,000, or 200 to 3,000, or 200 to 2,000, or 200 to 1,000, or 200 to 800, or 200 to 600, or 200 to 500, or 200 to 400, or 200 to 300, or 300 to 5,000, or 300 to 4,000, or 300 to 3,000, or 300 to 2,000, or 300 to 1,000, or 300 to 800, or 300 to 600, or 300 to 500, or 300 to 400, or 400 to 2,000, or 400 to 1,000, or 400 to 800, or 400 to 600, or 400 to 500, or 500 to 2,000, or 500 to 1,000, or 500 to 800, or 600 to 600 Daltons in an amount from 10 to 23, or 10 to 20, or 10 to less than 17, or 10 to 15, or 10 to 14, or 10 to 13, or 11 to 23, or 11 to 20, or 11 to less than 17, or 11 to 15, or 11 to 14, or 11 to 13, or 12 to 23, or 12 to 20, or 12 to less than 17, or 12 to 15, or 12 to 14, or 12 to 13, or 13 to 23, or 13 to 20, or 13 to less than 17, or greater than 15 to 23, or 17 to 23, or 17 to 20 wt %, based on the total weight of the cellulose ester composition.
In embodiments, the plasticizer composition comprises polyethylene glycol an average molecular weight of from 300 to 500 Daltons in an amount from 10 to 23, or 10 to 20, or 10 to less than 17, or 10 to 15, or 10 to 14, or 10 to 13, or 11 to 23, or 11 to 20, or 11 to less than 17, or 11 to 15, or 11 to 14, or 11 to 13, or 12 to 23, or 12 to 20, or 12 to less than 17, or 12 to 15, or 12 to 14, or 12 to 13, or 13 to 23, or 13 to 20, or 13 to less than 17, or greater than 15 to 23, or 17 to 23, or 17 to 20 wt %, based on the total weight of the cellulose ester composition; and the stabilizer composition comprises one or more secondary antioxidants in an amount from 0.01 to 0.8, or 0.05 to 0.6, or 0.05 to 0.55, or 0.05 to 0.5, or 0.05 to 0.4, or 0.05 to 0.3, or 0.07 to 0.6, or 0.07 to 0.55, or 0.07 to 0.5, or 0.07 to 0.4, or 0.07 to 0.3, or 0.08 to 0.6, or 0.08 to 0.55, or 0.08 to 0.5, or 0.08 to 0.4, or 0.08 to 0.3, or 0.1 to 0.6, or 0.1 to 0.55, or 0.1 to 0.5, or 0.1 to 0.4, or 0.1 to 0.3, or o.1 to 0.2, or 0.15 to 0.6, or 0.15 to 0.55, or 0.15 to 0.5, or 0.15 to 0.4, or 0.15 to 0.3, or 0.2 to 0.6, or 0.2 to 0.55, or 0.2 to 0.5, or 0.2 to 0.4 wt %, based on the total weight of the cellulose ester composition. In one class of this embodiment, the one or more secondary antioxidants comprises a phosphite compound (e.g., Weston 705T or Doverphos S-9228T), DLTDP or a combination thereof. In another class of this embodiment, the stabilizer composition further comprises one or more primary antioxidants (e.g., Irganox 1010 or BHT), citric acid or a combination thereof, wherein the one or more primary antioxidants are present in an amount from 0.1 to 0.5, or 0.1 to 0.4 wt %, based on the total weight of the cellulose acetate composition, and wherein the citric acid is present in an amount from 0.05 to 0.2, or 0.05 to 0.15 wt %, based on the total weight of the cellulose acetate composition.
In embodiments, the plasticizer composition comprises polyethylene glycol an average molecular weight of from 300 to 500 Daltons in an amount from 10 to less than 17, or 10 to 15, or 10 to 14, or 10 to 13, or 11 to less than 17, or 11 to 15, or 11 to 14, or 11 to 13, or 12 to less than 17, or 12 to 15, or 12 to 14, or 12 to 13, or 13 to less than 17, or 14 to less than 17, or 15 to less than 17 wt %, based on the total weight of the cellulose ester composition; and the stabilizer composition comprises one or more secondary antioxidants in an amount from 0.05 to 0.6, or 0.05 to 0.55, or 0.05 to 0.5, or 0.05 to 0.4, or 0.05 to 0.3, or 0.07 to 0.6, or 0.07 to 0.55, or 0.07 to 0.5, or 0.07 to 0.4, or 0.07 to 0.3, or 0.08 to 0.6, or 0.08 to 0.55, or 0.08 to 0.5, or 0.08 to 0.4, or 0.08 to 0.3, or 0.1 to 0.6, or 0.1 to 0.55, or 0.1 to 0.5, or 0.1 to 0.4, or 0.1 to 0.3, or o.1 to 0.2, or 0.15 to 0.6, or 0.15 to 0.55, or 0.15 to 0.5, or 0.15 to 0.4, or 0.15 to 0.3, or 0.2 to 0.6, or 0.2 to 0.55, or 0.2 to 0.5, or 0.2 to 0.4 wt %, based on the total weight of the cellulose ester composition.
In embodiments, the plasticizer composition comprises polyethylene glycol an average molecular weight of from 300 to 500 Daltons in an amount from greater than 15 to 23, or greater than 15 to 20 wt %, based on the total weight of the cellulose ester composition; and the stabilizer composition a first stabilizer component that comprises one or more secondary antioxidants in an amount from 0.05 to 0.6, or 0.05 to 0.55, or 0.05 to 0.5, or 0.05 to 0.4, or 0.05 to 0.3, or 0.07 to 0.6, or 0.07 to 0.55, or 0.07 to 0.5, or 0.07 to 0.4, or 0.07 to 0.3, or 0.08 to 0.6, or 0.08 to 0.55, or 0.08 to 0.5, or 0.08 to 0.4, or 0.08 to 0.3, or 0.1 to 0.6, or 0.1 to 0.55, or 0.1 to 0.5, or 0.1 to 0.4, or 0.1 to 0.3, or o.1 to 0.2, or 0.15 to 0.6, or 0.15 to 0.55, or 0.15 to 0.5, or 0.15 to 0.4, or 0.15 to 0.3, or 0.2 to 0.6, or 0.2 to 0.55, or 0.2 to 0.5, or 0.2 to 0.4 wt %, based on the total weight of the cellulose ester composition; and a second stabilizer component that comprises one or more primary antioxidants (e.g., Irganox 1010 or BHT), citric acid or a combination thereof, wherein the one or more primary antioxidants (if present) are present in an amount from 0.1 to 0.5, or 0.1 to 0.4 wt %, based on the total weight of the cellulose acetate composition, and wherein the citric acid (if present) is present in an amount from 0.05 to 0.2, or 0.05 to 0.15 wt %, based on the total weight of the cellulose acetate composition.
The present application also discloses a composition comprising: (1) a cellulose acetate, wherein the cellulose acetate has an acetyl degree of substitution (“DSAc”) in the range of from 2.2 to 2.6, and (2) from 17-23 wt % of a polyethylene glycol or a methoxy polyethylene glycol composition having an average molecular weight of from 300 Daltons to 550 Daltons, wherein the composition is melt processable, biodegradable, and disintegratable.
In one embodiment or in combination with any other embodiment, the composition comprises polyethylene glycol having an average molecular weight of from 300 to 500 Daltons.
In one embodiment or in combination with any other embodiment, the composition comprises polyethylene glycol having an average molecular weight of from 350 to 550 Daltons.
In one embodiment or in combination with any other embodiment, the cellulose acetate has a number average molecular weight (“Mn”) in the range of from 10,000 to 90,000 Daltons, as measured by GPC. In one embodiment or in combination with any other embodiment, the cellulose acetate has a number average molecular weight (“Mn”) in the range of from 30,000 to 90,000 Daltons, as measured by GPC. In one embodiment or in combination with any other embodiment, the cellulose acetate has a number average molecular weight (“Mn”) in the range of from 40,000 to 90,000 Daltons, as measured by GPC.
In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 5% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to the Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 10% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 20% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 30% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 50% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 70% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 30% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 50% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 70% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 95% disintegration after 12 weeks according to Disintegration Test protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, the composition further comprises at least one additional component chosen from a filler, an additive, a biopolymer, a stabilizer, or an odor modifier.
In one embodiment or in combination with any other embodiment, the composition further comprises a filler in an amount of from 1 to 60 wt %, based on the total weight of the composition. In one class of this embodiment, the filler is a carbohydrate, a cellulosic filler, an inorganic filler, a food byproduct, a desiccant, an alkaline filler, or combinations thereof.
In one subclass of this class, the filler is an inorganic filler. In one sub-subclass of this subclass, the inorganic filer is calcium carbonate.
In one subclass of this class, the filler is a carbohydrate. In one subclass of this class, the filler is a cellulosic filler. In one subclass of this class, the filler is a food byproduct. In one subclass of this class, the filler is a desiccant. In one subclass of this class, the filler is an alkaline filler.
In one embodiment or in combination with any other embodiment, the composition further comprises an odor modifying additive in an amount of from 0.001 to 1 wt %, based on the total weight of the composition. In one class of this embodiment, the odor modifying additive is vanillin, Pennyroyal M-1178, almond, cinnamyl, spices, spice extracts, volatile organic compounds or small molecules, or Plastidor. In one subclass of this class, the odor modifying additive is vanillin.
In one embodiment or in combination with any other embodiment, the composition further comprises a stabilizer in an amount from 0.01 to 5 wt %, based on the total composition. In one class of this embodiment, the stabilizer is a UV absorber, an antioxidant (e.g., ascorbic acid, BHT, BHA, etc.), an acid scavenger, a radical scavenger, an epoxidized oil (e.g., epoxidized soybean oil, epoxidized linseed oil, epoxidized sunflower oil), or combinations.
The present application also discloses an article comprising a composition comprising: (1) a cellulose acetate, wherein the cellulose acetate has an acetyl degree of substitution (“DSAc”) in the range of from 2.2 to 2.6, and (2) from 17-23 wt % of a polyethylene glycol or a methoxy polyethylene glycol composition having an average molecular weight of from 300 Daltons to 550 Daltons, wherein the composition is melt processable, biodegradable, and disintegratable.
In one embodiment or in combination with any other embodiment, the composition comprises polyethylene glycol having an average molecular weight of from 300 to 500 Daltons. In one embodiment or in combination with any other embodiment, the composition comprises polyethylene glycol having an average molecular weight of from 350 to 550 Daltons.
In one embodiment or in combination with any other embodiment, the article is formed from an orienting process, an extrusion process, an injection molding process, a blow molding process, or a thermoforming process. In one class of this embodiment, the article is formed from the orienting process. In one subclass of this class, the orienting process is a uniaxial stretching process or a biaxial stretching process.
In one class of this embodiment, the article is formed from the extrusion process. In one class of this embodiment, the article is formed from the injection molding process. In one class of this embodiment, the article is formed from the blow molding process. In one class of this embodiment, the article is formed from a thermoforming process. In one subclass of this class, the film or sheet used to form the article is from 10 to 160 mil thick.
In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 10%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 8%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 6%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 5%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 4%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 3%. In one embodiment, when the article is clear, the article exhibits a haze of less than 2%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 1%.
In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 5% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 10% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 20% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 30% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 50% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 70% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 30% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 50% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 70% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 95% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, the article exhibits greater than 30% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 50% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 70% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 80% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 95% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, the article has a thickness of 0.8 mm or less. In one embodiment, the article has a thickness of 0.76 mm or less.
In one embodiment or in combination with any other embodiment, the composition further comprises at least one additional component chosen from a filler, an additive, a biopolymer, a stabilizer, or an odor modifier.
In one embodiment or in combination with any other embodiment, the composition further comprises a filler in an amount of from 1 to 60 wt %, based on the total weight of the composition. In one class of this embodiment, the filler is a carbohydrate, a cellulosic filler, an inorganic filler, a food byproduct, a desiccant, an alkaline filler, or combinations thereof.
In one subclass of this class, the filler is an inorganic filler. In one sub-subclass of this subclass, the inorganic filer is calcium carbonate.
In one subclass of this class, the filler is a carbohydrate. In one subclass of this class, the filler is a cellulosic filler. In one subclass of this class, the filler is a food byproduct. In one subclass of this class, the filler is a desiccant. In one subclass of this class, the filler is an alkaline filler.
In one embodiment or in combination with any other embodiment, the composition further comprises an odor modifying additive in an amount of from 0.001 to 1 wt %, based on the total weight of the composition. In one class of this embodiment, the odor modifying additive is vanillin, Pennyroyal M-1178, almond, cinnamyl, spices, spice extracts, volatile organic compounds or small molecules, or Plastidor. In one subclass of this class, the odor modifying additive is vanillin.
In one embodiment or in combination with any other embodiment, the composition further comprises a stabilizer in an amount from 0.01 to 5 wt %, based on the total composition. In one class of this embodiment, the stabilizer is a UV absorber, an antioxidant (e.g., ascorbic acid, BHT, BHA, etc.), an acid scavenger, a radical scavenger, an epoxidized oil (e.g., epoxidized soybean oil, epoxidized linseed oil, epoxidized sunflower oil), or combinations.
The present application also discloses an article comprising a composition comprising: (1) a cellulose acetate, wherein the cellulose acetate has an acetyl degree of substitution (“DSAc”) in the range of from 2.2 to 2.6, (2) from 13-23 wt % of a polyethylene glycol or a methoxy polyethylene glycol composition having an average molecular weight of from 300 Daltons to 550 Daltons, and (3) 0.01-1.8 wt % of an additive chosen from an epoxidized soybean oil, a secondary antioxidant, or a combination, wherein the composition is melt processable, biodegradable, and disintegratable.
In one embodiment or in combination with any other embodiment, the additive is present at from 0.01 to 1 wt %, or 0.05 to 0.8 wt %, or 0.05 to 0.5 wt %, or 0.1 to 1 wt %.
In one embodiment or in combination with any other embodiment, the additive is an epoxidized soybean oil which is present at 0.1 to 1 wt %, or 0.1 to 0.5 wt %, or 0.5 to 1 wt %, or 0.3 to 0.8 wt %.
In one embodiment or in combination with any other embodiment, the additive is a secondary antioxidant which is present at 0.01 to 0.8 wt %, or 0.01 to 0.4 wt %, or 0.4 to 0.8 wt %, or 0.2 to 0.6 wt %.
In one embodiment or in combination with any other embodiment, the composition comprises polyethylene glycol having an average molecular weight of from 300 to 500 Daltons. In one embodiment or in combination with any other embodiment, the composition comprises polyethylene glycol having an average molecular weight of from 350 to 550 Daltons.
In one embodiment or in combination with any other embodiment, the article is formed from an orienting process, an extrusion process, an injection molding process, a blow molding process, or a thermoforming process. In one class of this embodiment, the article is formed from the orienting process. In one subclass of this class, the orienting process is a uniaxial stretching process or a biaxial stretching process.
In one class of this embodiment, the article is formed from the extrusion process. In one class of this embodiment, the article is formed from the injection molding process. In one class of this embodiment, the article is formed from the blow molding process. In one class of this embodiment, the article is formed from a thermoforming process. In one subclass of this class, the film or sheet used to form the article is from 10 to 160 mil thick.
In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 10%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 8%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 6%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 5%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 4%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 3%. In one embodiment, when the article is clear, the article exhibits a haze of less than 2%. In one embodiment or in combination with any other embodiment, when the article is clear, the article exhibits a haze of less than 1%.
In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 5% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 10% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 20% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 30% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 50% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 70% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 30% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 50% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 70% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 95% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, the article exhibits greater than 30% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 50% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 70% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 80% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 95% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, the article has a thickness of 0.8 mm or less. In one embodiment, the article has a thickness of 0.76 mm or less.
In one embodiment or in combination with any other embodiment, the composition further comprises at least one additional component chosen from a filler, an additive, a biopolymer, a stabilizer, or an odor modifier.
In one embodiment or in combination with any other embodiment, the composition further comprises a filler in an amount of from 1 to 60 wt %, based on the total weight of the composition. In one class of this embodiment, the filler is a carbohydrate, a cellulosic filler, an inorganic filler, a food byproduct, a desiccant, an alkaline filler, or combinations thereof.
In one subclass of this class, the filler is an inorganic filler. In one sub-subclass of this subclass, the inorganic filer is calcium carbonate.
In one subclass of this class, the filler is a carbohydrate. In one subclass of this class, the filler is a cellulosic filler. In one subclass of this class, the filler is a food byproduct. In one subclass of this class, the filler is a desiccant. In one subclass of this class, the filler is an alkaline filler.
In one embodiment or in combination with any other embodiment, the composition further comprises an odor modifying additive in an amount of from 0.001 to 1 wt %, based on the total weight of the composition. In one class of this embodiment, the odor modifying additive is vanillin, Pennyroyal M-1178, almond, cinnamyl, spices, spice extracts, volatile organic compounds or small molecules, or Plastidor. In one subclass of this class, the odor modifying additive is vanillin.
In one or more embodiments, the melt-processable biodegradable cellulose acetate composition of the present invention is a foamable composition, In one or more embodiments, the melt processable, biodegradable, foamable composition of the present invention includes (i) a biodegradable melt-stable cellulose acetate characterized by a heated intrinsic viscosity (HIV) of at least 0.9; (ii) a plasticizer; (iii) at least one nucleating agent; (iv) at least one blowing agent selected from the group consisting of a physical blowing agent and a chemical blowing composition comprising a chemical blowing agent and carrier polymer. In one or more embodiments, the melt processable, biodegradable, foamable composition of the present invention includes (i) a biodegradable melt-stable cellulose acetate characterized by a metals-to-sulfur molar ratio
M/S
of at least 1.35, wherein the M is the molar sum of metals selected from the group consisting of calcium, magnesium, potassium, sodium and combinations thereof and S is moles sulfur; (ii) a plasticizer; (iii) at least one nucleating agent; (iv) at least one blowing agent selected from the group consisting of a physical blowing agent and a chemical blowing composition comprising a chemical blowing agent and carrier polymer. In one or more embodiments, the foamable composition, comprising: (1) a cellulose acetate having a degree of substitution of acetyl (DSAc) between 2.2 to 2.6; (2) 5 to 40 wt % of a plasticizer; (3) 0.1 to 3 wt % of a nucleating agent; and (4) 0.1 to 3 wt % a chemical blowing composition, comprises: (i) 25 to 75 wt % of a blowing agent, and (ii) 25 to 75 wt % of a carrier polymer having a melting point that is no more than 150° C., wherein the proportions of the blowing agent and the carrier polymer are based on the total weight of the chemical blowing composition; wherein the proportions of the cellulose acetate, plasticizer, nucleating agent and chemical blowing composition are based on the total weight of the foamable composition.
In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 100° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 102° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 104° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 106° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 110° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 115° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA.
In one embodiment or in combination with any other embodiment, the blowing agent comprises sodium bicarbonate, citric acid or combination thereof. In one class of this embodiment, the blowing agent comprises sodium bicarbonate. In one class of this embodiment, the blowing agent comprises citric acid.
In one embodiment or in combination with any other embodiment, the carrier polymer comprises polybutylene succinate, polycaprolactone, or combinations thereof. In one class of this embodiment, the carrier polymer comprises polybutylene succinate. In one class of this embodiment, the carrier polymer comprises polycaprolactone.
In one embodiment or in combination with any other embodiment, the plasticizer comprises triacetin, triethyl citrate, or PEG400.
In one class of this embodiment, the plasticizer is present in a range of from 13 to 23, or 17 to 23 wt %. In one class of this embodiment, the plasticizer is present in a range of from 13 to 30, or 15 to 30 wt %.
In one class of this embodiment, the plasticizer comprises triacetin.
In one subclass of this class, the plasticizer is present in a range of from 13 to 23, or 15 to 23, or 17 to 23 wt %. In one subclass of this class, the plasticizer is present in a range of from 13 to 30, or 15 to 30 wt %.
In one class of this embodiment, the plasticizer comprises triethyl citrate. In one subclass of this class, the plasticizer is present in a range of from 13 to 23, or 15 to 23, or 17 to 23 wt %. In one subclass of this class, the plasticizer is present in a range of from 13 to 30, or 15 to 30 wt %.
In one class of this embodiment, the plasticizer comprises PEG400. In one subclass of this class, the plasticizer is present in a range of from 13 to less than 17, or 17 to 23 wt %. In one subclass of this class, the plasticizer is present in a range of from 13 to 30, or 15 to 30 wt %.
In one embodiment or in combination with any other embodiment, the nucleating agent comprises a magnesium silicate, a silicon dioxide, a magnesium oxide, or combinations thereof. In one class of this embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one class of this embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one class of this embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one class of this embodiment, the nucleating agent comprises a magnesium silicate. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one class of this embodiment, the nucleating agent comprises a silicon dioxide. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one class of this embodiment, the nucleating agent comprises a magnesium oxide. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one embodiment or in combination with any other embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a fiber. In one class of this embodiment, the fiber comprises hemp, bast, jute, flax, ramie, kenaf, sisal, bamboo, or wood cellulose fibers. In one subclass of this class, the fiber comprises hemp.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a photodegradation catalyst. In one class of this embodiment, the photodegradation catalyst is a titanium dioxide, or an iron oxide. In one subclass of this class, the photodegradation catalyst is a titanium dioxide. In one subclass of this class, the photodegradation catalyst is an iron oxide.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a pigment. In one class of this embodiment, the pigment is a titanium dioxide, a carbon black, or an iron oxide. In one subclass of this class, the pigment is a titanium dioxide. In one subclass of this class, the pigment is a carbon black. In one subclass of this class, the pigment is an iron oxide.
In one embodiment or in combination with any other embodiment, the foamable composition is biodegradable.
In one embodiment or in combination with any other embodiment, the foamable composition comprises two or more cellulose acetates having different degrees of substitution of acetyl.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a biodegradable polymer that is different than the cellulose acetate.
In one embodiment or in combination with any other embodiment, there is an article prepared from the any one of the previously described foamable compositions, wherein the article is a foam or a foam article.
In one class of this embodiment, the article has a thickness of up to 3 mm.
In one class of this embodiment, the article has one or more skin layers. The skin layer may be found on the outer surface of the article or foam. The skin layer can also be found in the middle of the foam.
In one class of this embodiment, the article is biodegradable.
In one or more embodiments, in particular for embodiments wherein the article is a foam or a foam article, density of the foam is an important parameter insofar as it can influence various article performance properties such as water barrier, stiffness and thermal conductivity. In one class of this embodiment, the article has a density or the article includes foam with a density less than 0.9 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.8 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.7 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.6 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density Of less than 0.5 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.4 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.3 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.2 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.1 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density of less than 0.05 g/cm3. In one class of this embodiment, the article has a density or the article includes foam with a density in the range of from 0.2 to 0.9 g/cm3. In one or more embodiments, the article has a density or the article includes foam with a density of from 0.01 to 0.2 g/cm3.
In one class of this embodiment, the article is industrial compostable or home compostable. In one subclass of this class, the article is industrial compostable. In one sub-subclass of this subclass, the article has a thickness that is less than 1.1 mm. In one subclass of this class, the article is home compostable. In one sub-subclass of this subclass, the article has a thickness that is less than 1.1 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 0.8 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 0.6 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 0.4 mm.
In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a foam having a thickness of 0.38 mm, the foam exhibits greater than 5% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to the Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a foam having a thickness of 0.38 mm, the foam exhibits greater than 10% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a foam having a thickness of 0.38 mm, the foam exhibits greater than 20% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a foam having a thickness of 0.38 mm, the foam exhibits greater than 30% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a foam having a thickness of 0.38 mm, the foam exhibits greater than 50% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, wherein when the composition is formed into a foam having a thickness of 0.38 mm, the foam exhibits greater than 70% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
In one embodiment or in combination with any other embodiment, when the composition is formed into a foam having a thickness of 0.76 mm, the foam exhibits greater than 30% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a foam having a thickness of 0.76 mm, the foam exhibits greater than 50% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a foam having a thickness of 0.76 mm, the foam exhibits greater than 70% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a foam having a thickness of 0.76 mm, the foam exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, when the composition is formed into a foam having a thickness of 0.76 mm, the foam exhibits greater than 95% disintegration after 12 weeks according to Disintegration Test protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
The present application discloses a foamable composition comprising: (1) a cellulose acetate having a degree of substitution of acetyl (DSAc) between 2.2 to 2.6; (2) 5 to 40 wt % of a plasticizer; (3) 0.1 to 3 wt % of a nucleating agent; and (4) 0.1 to 15 wt % of a physical blowing agent, wherein the proportions of the cellulose acetate, plasticizer, nucleating agent and physical blowing agent are based on the total weight of the foamable composition.
In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 100° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 102° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 104° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 106° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 110° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA. In one embodiment or in combination with any other embodiment, the foamable composition exhibits a heat deflection temperature of greater than 115° C. as measured at 0.45 MPa at 2% elongation with a 1 Hz frequency using a DMA.
In one embodiment or in combination with any other embodiment, the physical blowing agent comprises CO2, N2, unbranched or branched (C2-6)alkane, or any combination thereof. In one class of this embodiment, the physical blowing agent comprises CO2. In one class of this embodiment, the physical blowing agent comprises N2. In one class of this embodiment, the physical blowing agent comprises unbranched or branched (C2-6)alkane.
In one embodiment or in combination with any other embodiment, the physical blowing agent is present from 0.1 to 0.5 wt %. In one embodiment or in combination with any other embodiment, the physical blowing agent is present from 0.5 to 4 wt %. In one embodiment or in combination with any other embodiment, the physical blowing agent is present from 0.3 to 4 wt %. In one embodiment or in combination with any other embodiment, the physical blowing agent is present from 4 to 10 wt %.
In one embodiment or in combination with any other embodiment, the plasticizer comprises triacetin, triethyl citrate, or PEG400.
In one class of this embodiment, the plasticizer is present in a range of from 17 to 23 wt %. In one class of this embodiment, the plasticizer is present in a range of from 15 to 30 wt %.
In one class of this embodiment, the plasticizer comprises triacetin.
In one subclass of this class, the plasticizer is present in a range of from 17 to 23 wt %. In one subclass of this class, the plasticizer is present in a range of from 15 to 30 wt %.
In one class of this embodiment, the plasticizer comprises triethyl citrate. In one subclass of this class, the plasticizer is present in a range of from 17 to 23 wt %. In one subclass of this class, the plasticizer is present in a range of from 15 to 30 wt %.
In one class of this embodiment, the plasticizer comprises PEG400. In one subclass of this class, the plasticizer is present in a range of from 17 to 23 wt %. In one subclass of this class, the plasticizer is present in a range of from 15 to 30 wt %.
In one embodiment or in combination with any other embodiment, the nucleating agent comprises a magnesium silicate, a silicon dioxide, a magnesium oxide, or combinations thereof. In one class of this embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one class of this embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one class of this embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one class of this embodiment, the nucleating agent comprises a magnesium silicate. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one class of this embodiment, the nucleating agent comprises a silicon dioxide. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one class of this embodiment, the nucleating agent comprises a magnesium oxide. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. In one subclass of this class, the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one embodiment or in combination with any other embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 2 microns. In one embodiment, the nucleating agent comprises a particulate composition with a median particle size less than 1.5 microns. the nucleating agent comprises a particulate composition with a median particle size less than 1.1 microns.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a fiber. In one class of this embodiment, the fiber comprises hemp, bast, jute, flax, ramie, kenaf, sisal, bamboo, or wood cellulose fibers. In one subclass of this class, the fiber comprises hemp.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a photodegradation catalyst. In one class of this embodiment, the photodegradation catalyst is a titanium dioxide, or an iron oxide. In one subclass of this class, the photodegradation catalyst is a titanium dioxide. In one subclass of this class, the photodegradation catalyst is an iron oxide.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a pigment. In one class of this embodiment, the pigment is a titanium dioxide, a carbon black, or an iron oxide. In one subclass of this class, the pigment is a titanium dioxide. In one subclass of this class, the pigment is a carbon black. In one subclass of this class, the pigment is an iron oxide.
In one embodiment or in combination with any other embodiment, the foamable composition is biodegradable.
In one embodiment or in combination with any other embodiment, the foamable composition comprises two or more cellulose acetates having different degrees of substitution of acetyl.
In one embodiment or in combination with any other embodiment, the foamable composition further comprises a biodegradable polymer that is different than the cellulose acetate.
In one embodiment or in combination with any other embodiment, there is an article prepared from the any one of the previously described foamable compositions, wherein the article is a foam or a foam article. In one or more embodiments, the foam article is formed from or includes a foam of the present invention.
In one class of this embodiment, the article has a thickness or foam thickness of up to 3 mm.
In one class of this embodiment, the article has one or more skin layers.
In one class of this embodiment, the article is biodegradable.
In one class of this embodiment, the article includes foam with a density less than 0.9 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density, of less than 0.8 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density of less than 0.7 g/cm3. In one class of this embodiment, the article has a density of less than 0.6 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density, of less than 0.5 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density, of less than 0.4 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density of less than 0.3 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density of less than 0.2 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density, of less than 0.1 g/cm3. In one class of this embodiment, the article has a density, or the article includes foam with a density of less than 0.05 g/cm3. In one class of this embodiment, the article has a density in the range of from 0.2 to 0.9 g/cm3.
In one class of this embodiment, the article is industrial compostable or home compostable. In one subclass of this class, the article is industrial compostable. In one sub-subclass of this subclass, the article has a thickness that is less than 6 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 3 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 1.1 mm. In one subclass of this class, the article is home compostable. In one sub-subclass of this subclass, the article has a thickness that is less than 6 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 3 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 1.1 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 0.8 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 0.6 mm. In one sub-subclass of this subclass, the article has a thickness that is less than 0.4 mm.
In one embodiment or in combination with any other embodiment, the article has a thickness that is less than 6 mm. In one embodiment or in combination with any other embodiment, the article has a thickness that is less than 3 mm. In one embodiment or in combination with any other embodiment, the article has a thickness that is less than 1.1 mm. In one embodiment or in combination with any other embodiment, the article has a thickness that is less than 0.8 mm. In one embodiment or in combination with any other embodiment, the article has a thickness that is less than 0.6 mm. In one embodiment or in combination with any other embodiment, the article has a thickness that is less than 0.4 mm.
The present application discloses a method for preparing a foamable composition comprising: (a) providing a nonfoamable composition comprising (1) a cellulose acetate having a degree of substitution of acetyl (DSAc) between 2.2 to 2.6, (2) 5 to 40 wt % of a plasticizer, and (3) 0.1 to 3 wt % of a nucleating agent; (b) melting the nonfoamable composition in an extruder to form a melt of the nonfoamble composition; and (b) injecting a physical blowing agent into the melt of the nonfoamable composition to prepare a melted foamable composition.
In one embodiment or in combination with any other embodiment, the physical blowing agent comprises CO2, N2 or an unbranched or branched (C2-6)alkane.
In one embodiment or in combination with any other embodiment, the article exhibits greater than 30% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 50% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 70% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 80% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013). In one embodiment or in combination with any other embodiment, the article exhibits greater than 95% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification or in the alternative according to ISO 16929 (2013).
Embodiment 1. A foamable composition, comprising: (1) a stabilized cellulose acetate having an HIV of at least 0.9, M/S of at least 1.35 and a degree of substitution of acetyl (DSAc) between 2.2 to 2.6; (2) 5 to 40 wt % of a plasticizer; (3) 0.1 to 3 wt % of a nucleating agent; and (4) 0.1 to 3 wt % a chemical blowing composition, comprises: (i) 25 to 75 wt % of a blowing agent, and (ii) 25 to 75 wt % of a carrier polymer having a melting point that is no more than 150° C., wherein the proportions of the blowing agent and the carrier polymer are based on the total weight of the chemical blowing composition, wherein the proportions of the cellulose acetate, plasticizer, nucleating agent and chemical blowing composition are based on the total weight of the foamable composition.
Embodiment 2. The foamable composition of any one of Embodiment 1, wherein the blowing agent comprises sodium bicarbonate, citric acid or combination thereof.
Embodiment 3. The foamable composition of any one of Embodiments 1-2, wherein the carrier polymer comprises a polybutylene succinate, a polycaprolactone, or combinations thereof.
Embodiment 4. A foamable composition comprising: (1) a cellulose acetate having a degree of substitution of acetyl (DSAc) between 2.2 to 2.6; (2) 5 to 40 wt % of a plasticizer; (3) 0.1 to 3 wt % of a nucleating agent; and (4) 0.1 to 15 wt % of a physical blowing agent, wherein the proportions of the cellulose acetate, plasticizer, nucleating agent and physical blowing agent are based on the total weight of the foamable composition.
Embodiment 5. A foamable composition comprising: (1) a cellulose acetate having a degree of substitution of acetyl (DSAc) between 2.2 to 2.6; (2) 5 to 40 wt % of a plasticizer; (3) 0.1 to 3 wt % of a nucleating agent; and (4) 1 to 15 wt % of a physical blowing agent, wherein the proportions of the cellulose acetate, plasticizer, nucleating agent and physical blowing agent are based on the total weight of the foamable composition.
Embodiment 6. The foamable composition of any one of Embodiments 4 or 5, wherein the physical blowing agent comprises CO2, N2, unbranched or branched (C2-6)alkane, or any combination thereof.
Embodiment 7. The foamable composition of any one of Embodiments 1-6, wherein the plasticizer comprises triacetin, triethyl citrate, or PEG400.
Embodiment 8. The foamable composition of any one of Embodiments 1-7, wherein the plasticizer is present from 17 to 23 wt %.
Embodiment 9. The foamable composition of any one of Embodiments 1-8, wherein the nucleating agent comprises a particulate composition with a median particle size less than 2 microns.
Embodiment 10. The foamable composition of any one of Embodiments 1-9, wherein the nucleating agent comprises a magnesium silicate, a silicon dioxide, a magnesium oxide, or combinations thereof.
Embodiment 11. The foamable composition of any one of Embodiment 1-10, wherein the foamable composition further comprises a fiber.
Embodiment 12. The foamable composition of Embodiment 11, wherein the fiber is biodegradable.
Embodiment 13. The foamable composition of any one of Embodiments 11-12, wherein the fiber comprises hemp, bast, jute, flax, ramie, kenaf, sisal, bamboo, or wood cellulose fibers.
Embodiment 14. The foamable composition of any one of Embodiment 1-13, wherein the foamable composition further comprises a photodegradation catalyst.
Embodiment 15. The foamable composition of Embodiment 14, wherein the photodegradation catalyst is a titanium dioxide, or an iron oxide.
Embodiment 16. The foamable composition of any one of Embodiment 1-15, wherein the foamable composition further comprises a pigment.
Embodiment 17. The foamable composition of Embodiment 16, wherein the pigment is a titanium dioxide, carbon black, or an iron oxide.
Embodiment 18. The foamable composition of any one of Embodiment 1-17, wherein the foamable composition is biodegradable.
Embodiment 19. The foamable composition of any one of Embodiment 1-18, wherein the foamable composition comprises two or more cellulose acetates having different degrees of substitution of acetyl.
Embodiment 20. The foamable composition of any one of Embodiment 1-19, wherein the foamable composition further comprises a biodegradable polymer that is different than the cellulose acetate.
Embodiment 21. The composition of any one of Embodiments 1-20, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 5% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification.
Embodiment 22. The composition of any one of Embodiments 1-20, wherein when the composition is formed into a film having a thickness of 0.38 mm, the film exhibits greater than 10% disintegration after 6 weeks and greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification.
Embodiment 23. The composition of any one of Embodiments 1-20, wherein when the composition is formed into a film having a thickness of 0.76 mm, the film exhibits greater than 90% disintegration after 12 weeks according to Disintegration Test Protocol, as described in the specification.
Embodiment 24. An article prepared from the foamable composition of any one of claims 1-23, wherein the article is a foam.
Embodiment 25. The article of Embodiment 24, wherein the article has a thickness of up to 6 mm.
Embodiment 26. The article of anyone of Embodiments 24-25, wherein the article has one or more skin layers.
Embodiment 27. The article of any one of Embodiments 24-26, wherein the article is biodegradable.
Embodiment 28. The article of any one of Embodiments 24-27, wherein the article has a density less than 0.9 g/cm3.
Embodiment 29. The article of any one of Embodiments 24-28, wherein the article is industrial compostable or home compostable.
Embodiment 30. The article of Embodiment 29, wherein the thickness is less than 3 mm.
Embodiment 31. The article of any one of Embodiments 24-30, wherein the article exhibits greater than 90% disintegration after 12 weeks according to disintegration test protocol for films, as described in the specification.
BHT is butylated hydroxytoluene or Tenox BHT (Eastman); bioCBA is biodegradable chemical blowing agent; CA is cellulose acetate; CA398-30 is Eastman cellulose acetate CA398-30; CA398-10 is Eastman cellulose acetate CA398-10; CBA is chemical blowing agent; CDA is cellulose diacetate; CAPA 6500 is polycaprolactone (Ingevity); CE41972 is Eastman cellulose acetate Cellulose Ester 41972 or Cellulose Ester FE700; DLTDP is dilauryl thiodipropionate (Sigma Aldrich); DMA or DMTA is dynamic mechanical analysis; DS is degree of substitution per anhydroglucose unit of a cellulose ester; EOB is elongation at break; EPSO is epoxidized soybean oil (Vikoflex 7170, Arkema); FZ 73S is Foamazol 73s (Bergen International); FZ 95 is Foamazol 95 (Bergen International); h or hr is hour(s); HDT is heat deflection temperature; HK40B is Hydrocerol HK40B (Clariant); PHB(6)Hx=poly(3-hydroxybutyrate-co-6 mol %-3-hydroxyhexanoate) having an average Mw of about 770,000 (measured using GPC and PS standards with methylene chloride solvent); Pz is plasticizer; TA is triacetin; TEC is triethyl citrate; ° C. is degree(s) Celsius; wt % is weight percent; PEG400 is polyethylene glycol with an average molecular weight of 400 Daltons. kWh/kg is kilowatt hour per kilogram; L is liters; oz is ounce; PBA is physical blowing agent; PBS is polybutylene succinate; PCL is polycaprolactone; PS is polystyrene; rpm is revolutions per minute; TGA is thermal gravimetric analysis; MW is molecular weight.
Starting CDA materials were obtained from Eastman Chemical Company. The materials included commercially available CDA having a DS of 2.5 and Mn of about 50,000 and about 40,000 (CA398-30 and CA398-10) and commercially manufactured CDA having a DS of 2.2. CDA compositions with Pz were prepared. The plasticizer used in the examples was TA. TA pre-plasticized compositions were also compounded into additional compositions with fillers or polymeric additives. Cellulose acetate compositions were made with a polymeric additive that was polyethylene glycol having an average molar mass of about 400 g/mol (“PEG-400”) and no TA plasticizer. Plasticized cellulose acetate resin was prepared by feeding cellulose diacetate to a twin screw co-rotating extruder using loss in weight feeders for the solids and liquid feeds. The solids were fed into the feed throat of the extruder and liquids were injected into the first heated barrel zone. The materials were compounded using an increasing temperature profile from 70° C. in the 1st heated zone to 230° C. at the die. The materials were processed at conditions sufficient to provide a relatively homogeneous resin mixture. The resulting resin was a pre-plasticized cellulose acetate resin with either 15, 17 or 30 wt % TA as plasticizer. The cellulose acetate composition with PEG400 was made in a similar manner.
In the case of compounded CDA compositions, the (TA) pre-plasticized cellulose acetate resin with 15, 17 or 30 wt % TA as plasticizer (base resin) was compounded with filler material or polymeric additive. The compounding was performed on a 26 mm twin screw extruder with side feeders. The base resin was fed into a barrel on the extruder through a loss in weight feeder system. Filler materials or polymeric additives were added through a side feeder with a loss in weight feeder system. The zone 1 temperature was set at 150° C. as well as all subsequent zones plus the die was set at 180° C. Specific energy input (SEI) varied between 0.116 kWh/kg and 0.158 kWh/kg for these compounds. Melt temperatures were between 177° C. and 181° C. (measured in the die). Atmospheric venting was performed after the first kneading section and prior to the pumping section to vent steam from the undried base polymer and water associated with the filler materials. The final product composition was produced by passing through a die to produce strands that were cut into pellets.
A 1.5 inch Killion single screw extruder equipped with Maddock mixer screw was utilized to produce films. Cellulose acetate composition pellets were loaded into the hopper and material passed into the barrel where the Maddock screw transferred the material toward the die. The barrel (housing the screw) was heated in three zones so that the pellets would melt as they passed over the screw along a very narrow clearance allowing for a high shear and high degree of dispersive mixing. It was observed that a homogeneous polymer mixture was formed as it approached the die and the mixture was forced through the die by the screw where extrusion occurs. The extrusion formed a flat molten film as the film exited the die and the film solidified on temperature controlled polished chrome rolls (the roll stack).
Post-extrusion film samples were removed intermittently to determine film thickness. When the extruder was producing the proper film thickness, the film was attached to a receiving roller and the film was carefully wound until the final roll was complete.
A test method used for disintegration was based on ISO 16929 Plastics—Determination of the Degree of Disintegration of Plastics Materials under Defined Composting Conditions in a Pilot-Scale Test (2013). A pilot-scale aerobic composting test was used to simulate as closely as possible a real and complete composting process in composting bins of 200 L. The test materials (films) were put into slide frames that exposed approximately 8.05 cm2 of test material on both sides of the film. These slide frames were then mixed with biowaste and composted in two 200-liter composting bins. The biowaste consisted of Vegetable, Garden and Fruit waste (VGF) to which 11% extra structural material was added in order to obtain optimal composting conditions. Consistent with full-scale composting, inoculation and temperature increase happened spontaneously. The test was considered valid only if the maximum temperature during composting was above 60° C. and below 75° C., and if the daily temperature remained above 40° C. during at least 4 weeks. The composting process was directed through air flow and moisture content. The temperature and exhaust gas composition were regularly monitored. The composting process was continued until fully stabilized compost was obtained (3 months). During composting, the contents of the vessels were manually turned, at which time test item were retrieved and visually evaluated.
CA398-30 was the resin for all tests (DS=2.52; mp 230-250 C, Tg 189 C). Solutions were made containing 12% CA398-30 in acetone. Additives were included in the solution as indicated. Some mixtures were heated to 50 C to promote dissolution and mixing. Thin films (˜3 mil), were drawn down on a clean glass plate using a film applicator (BYK 5351; 2″ square frame, 5-50 mils). Thicker films (5 to 40 mil) were cast from acetone into flat-bottom aluminum dishes, and solvent evaporation was controlled over 16 to 24 h by covering the pans. Film thickness was measured with a digital micrometer (Mitutoyo Digimatic Micrometer, MDC-1″ PX) with 0.05 mil resolution.
Glass transition temperature (Tg) was estimated by both Differential Scanning Calorimetry (DSC) and by DMA. DMA of the films consisted of a normal temperature sweep at one frequency controlling oscillating strain, to collect information about both room temperature differences and Tg differences. For DMA, film samples were run at 3° C. per min under 0.1% strain at 1 Hz and the Tg range was estimated from the E′ onset and the peak of the Tan(Delta) curve.
Tg (DSC) of 10 Mil Films with PEG MW 200 to 2000
PEG with MW ranging from 200 to 8,000 was added at 17.0 wt % to a CA398-30 dope (12 wt % CA398-30 in acetone) and incorporated by heating at up to 50° C. Films were cast with a 10 mil dry thickness. Tg of the CA398-30/PEG blends was estimated by DSC 2nd heat, and the results are summarized in Table 1. When the PEG MW was 6,000 or greater, incompatibility in the films was observed as defects in the films. When the PEG MW was 2,000 or greater, no Tg was detected in the 2nd heat during DSC. Instead, an endotherm was detected at a temperature close to the melting point of the PEG, a sign of immiscibility of the blend. A single Tg was detected in CA/PEG blends when the PEG MW was 600 or lower.
Measuring Tg of thin films plasticized with PEG and PEG derivatives is not straightforward, and a clear glass transition temperature of cellulosic materials is sometimes difficult to observe by DSC. When a more sensitive technique is needed, DMTA or DMA is an option.
Table 2 and 3 provide Tg values using the DMA method for CA398-30) films plasticized at 23 wt % and 17 wt %, respectively. The Tan(delta) was used as an estimate of the Tg values for the films. At 23 wt % plasticizer loading (Table 2), PEG600, MPEG165, MPEG165, MPEG550, and MPEG750 exhibited Tg values of greater than 160° C. as measured by DMA. On the other hand, PEG200, PEG300, PEG400, MPEG350, MEPG450 exhibited Tg values of from 113° C. to 120° C., indicating greater plasticization efficiency.
For plasticizer loading at 17 wt % (Table 3), PEG400, MPEG350 and MPEG550 exhibited a Tg range of from 127° C. to 132° C. However, PEG600 exhibited a Tg of 195.6° C., which is similar to unplasticized CA398-30.
The low MW of plasticizers are susceptible to volatilization during thermal processing, either during compounding, extrusion or thermoforming. Isothermal volatility was tested on different film formulations. CA398-30: DS=2.5; mp 230-250, Tg 189 C (DSC). Thin films (˜3 mil) were cast onto glass plates from a 12 wt % solution of CA398-30 and plasticizer in acetone. The solvent was evaporated, and the films equilibrated under lab conditions (20-23 C, 25-30% RH). Films with 23.0 wt % PZ (1-inch squares, equilibrated to lab ambient conditions, 20-23° C. and ˜25% RH), were accurately weighed before and after being heated to 120° C. for 7 min to 127 min to monitor weight loss. The results in Table 4 show that PEG200 is the most volatile plasticizer in the 5 mil films, followed by TA and TEC (not shown in Table). Weight loss of films plasticized with PEG400, PEG600, Polysorbate 20 (Tween 20) was not different from un-plasticized CA398-30.
Stress Whitening after Biaxial Stretching
The films of Ex 16 were subjected to stretching to mimic thermoforming. To understand the sheet temperature effect, two oven temperatures are chosen at 165° C. and 185° C. The heating time is fixed at 40 seconds before stretching. To mimic the areal draw ratio of a 12 oz clam shell, an equivalent biaxial draw ratio 1.5×1.5 is used. For a 12 oz drinking cup, an equivalent biaxial draw ratio 2×2 is used. Two strain rates are also selected. One is at 50%/s which is about the same strain rate in vacuum forming @ 25 in Hg. The other is 500%/s which approximates the high speed stretching from a plug. Since stress whitening is the main focus in this example, the key response is thus haze in the sheet which is proportional to degree of stress whitening.
The formation of stress whitening was in thermoforming CDA sheet into clam shell (hinged container) or cup. To mimic vast packaging containers in different shapes and sizes, an equivalent biaxial draw ratio is calculated by using the areal draw ratio of the container. Table 5 shows two examples. One is for a 12 oz drink cup which has an aerial draw ratio of 4.45 whose approximate biaxial draw ratio is about 2×2. The other is a 12 oz clam shell which has an aerial draw ratio of 1.93 whose approximate biaxial ratio is about 1.5×1.5. The areal draw ratio is defined by the total surface area of the formed container divided by the original sheet area before forming.
To explore the effect of each variable on the stress whitening in biaxially stretched CDA sheets, Table 6 is the experimental matrix. The haze of each sample will be measured by changing the thickness, draw ratio, stretching temperature, and strain rate.
Haze of 15 Mil Samples after Stretching
At a lower draw ratio 1.5×1.5, 15 mil Ex 13 samples show little haze under various stretching conditions as shown in Table 7. Ex 15 (15 mil) samples on the other hand develop some haze at the same stretching conditions especially at 165° C. Table 7 summarizes the results from biaxial stretching of 15 mil thick samples, Ex 13 demonstrates little haze formation even it is subjected to a higher draw ratio, strain rate and lower temperature while obvious haze is observed for Ex 15 at the same combined stretching conditions.
Table 8 summarizes the results for 30 mil thick samples, Ex 14 demonstrates little haze formation even though it is subjected to a higher draw ratio, strain rate and lower temperature while significant haze is observed for Ex 16 at the same combined stretching conditions.
In films Ex 15 and Ex 16, due to stress whitening issue, only shallow drawn articles can be vacuum formed using this formulation.
The gel count was determined by adapting ASTM D7310-11. The film samples were imaged using an Allied Vision Technologies GT2750C Ethernet based camera. The area being analyzed is 5 cm×5 cm=25 cm2, taking 6 images with a total area imaged of 150 cm2. The camera is a color camera with a 2750×2200 1 inch pixel sensor. The camera utilizes the default settings except the exposure time is set to 400 microseconds. The lens used in the system is an Opto Engineering TC23080 bi-telecentric lens. The working distance of the lens is 226.7 mm. This generates a field of view that is 76.5 mm×64.0 mm. The light used in the setup is an Opto Engineering LTCLHP080-G collimated light. The light was positioned 150 mm away from the sample. The light and lens are setup in transmission mode so that the film sample rests between the light and lens. The transmission mode layout coupled to telecentric optics provides unique advantages over other lighting geometry/lens combinations. The combination of transmission mode coupled to telecentric optics causes translucent gels present in a translucent film to appear as dark particles on the image sensor. The appearance of gels as dark particles on a translucent background enables easy detection, counting, and metrology of gels.
Images from the camera were acquired using National Instruments Measurement and Automation Explorer software. The images were processed using an internally developed program written in the LabVIEW programming language. In general, the image processing program isolates individual gels in the film. The first step the program performs is a color plane extraction. When an image is collected with a color camera there are several images created in different planes. The color plane extracted for this method was the HSI intensity plane because this color plane gave the best contrast between the background and defects of interest. The next step performed in the image processing routine is calibration of the image. Calibration of the image is used to convert the pixels into real world units. An imaging standard is used to perform this calibration. The saved calibration is then applied in this step to all subsequent images. The image is then threshold using a local background corrected algorithm with a local area of 32×32 pixels. This automated thresholding routine performs a background correction to eliminate non-uniform lighting effects. The interclass variance thresholding algorithm is then applied to isolate dark particles. In the interclass variance method for thresholding the interclass variance is measured at every possible pixel intensity. The threshold is set at a pixel intensity such that the interclass variance is maximized. The algorithm assumes that the pixel intensities represent a bimodal distribution with 2 classes. The image is a binary image at this point in the processing routine. The particles in the image are given a value of 1 and the background is given a value of 0. An opening function is applied to the particles. The opening function first erodes particles and then dilates the remaining particles. The larger particles remain, but small particles are eliminated. This step is done to eliminate sensor noise and to disconnect neighboring particles that may be touching. The next step eliminates particles that are touching the border of the image because these particles cannot be accurately measured. Once the border particles are eliminated the area of all gel particles is summed. The area imaged coupled to the area of the gels can be used to calculate the total particle/gel area of the film sample.
CA398-30 was compounded with either PEG400 or PEG600 at the desired weight percentage and subsequently formed into pellets. A twin screw extruder was used to first prepare compounded pellets with the extruder having the conditions as shown in Table 9. Before using the pellets for extruding the films, the pellets were dried at 140° C. for 4 h. The dried compounded pellets were then used to extrude the pellets using an extruder having the following conditions shown in Table 10.
Ex 17: Film (80 wt % CA398-30, 20 wt % PEG400, 30 mil)
Ex 18: Film (80 wt % CA398-30, 20 wt % PEG400, 15 mil)
Ex 19: Film (80 wt % CA398-30, 20 wt % PEG600, 30 mil)
Ex 20: Film (80 wt % CA398-30, 20 wt % PEG600, 15 mil)
Pilot-scale aerobic composting tests were conducted (as described above). In the tests, the film sample was mixed with fresh organic pre-treated municipal solid waste (biowaste) and introduced to an insulated composting bin, at which time composting spontaneously began. The film samples tested included: 15 mil thick extruded films of cellulose diacetate plasticized with 15 wt % TA, 1 wt % EPSO, and no filler (Ex 1); and 15 mil thick extruded films of cellulose diacetate plasticized with 15 wt % TA and compounded with 1 wt % EPSO and 15 wt % calcium carbonate (Omyacarb UF-FL CaCO3, surface treated and having a particle size of 0.70 microns) (Ex 2). The films were prepared as discussed above. The samples were observed after 1, 2, 3, 4, 6, 8, 10 and 12 weeks of composting. The disintegration results for Ex 1 and 2 are summarized in Table 12.
The films made from compositions containing 15 wt % calcium carbonate had faster disintegration. Although not shown, a similar effect was observed for films with 30 wt % TA, where films with 30 wt % TA disintegrated faster than otherwise similar films with 15 wt % TA.
Film samples were tested as follows: 10 mil thick extruded films of cellulose diacetate having an acetyl degree of substitution (DS) of 2.5 and Mn of 50,000 plasticized with 15 wt % TA, 1 wt % EPSO, and no filler (Ex 3); and 10 mil thick extruded films of cellulose diacetate having an acetyl degree of substitution (DS) of 2.2 plasticized with 15 wt % TA, 1 wt % EPSO, and no filler (Ex 4). The films were prepared as discussed above. The samples were observed after 1, 2, 3, 4, 6, 8, 10 and 12 weeks of composting. The results of Ex 3 and 4 are summarized in Table 12.
A review of the results reveals that the films with a lower acetyl level CDA will disintegrate faster than a similar film with a higher acetyl content CDA.
Film samples were tested as follows: 10 mil thick extruded films of cellulose diacetate having a number average molecular weight (Mn) of 40,000 (measured by GPC as described herein) plasticized with 15 wt % TA, 1 wt % EPSO, and no filler. The films were prepared as discussed above. The samples were observed after 1, 2, 3, 4, 6, 8, 10 and 12 weeks of composting. The results of Ex 5 are also summarized in Table 12.
The results reveal that the films with a lower molecular weight CDA will disintegrate faster than a similar film with a higher molecular weight CDA.
Plasticizer and polymeric additives.
The film samples tested included: 20 mil thick extruded films of cellulose diacetate plasticized with 17 wt % TA and compounded with 1 wt % EPSO and 20 wt % PHB(6)Hx (Ex 6); and 20 mil thick extruded films of cellulose diacetate plasticized with 17 wt % TA and compounded with 1 wt % EPSO, 20 wt % PHB(6)Hx and 10 wt % CAPA 6500 (Ex 7). The results are summarized in Table 12.
The film samples tested included: 15 and 30 mil thick extruded films of cellulose diacetate compounded with 1 wt % EPSO and 10, 15, or 20 wt % PEG-400. The results are summarized in Table 12.
The film samples tested included: 20 mil thick extruded films of cellulose diacetate plasticized with 20 wt % TA and compounded with 1 wt % talc and 1 wt % EPSO by compounding the components in a manner similar to methods discussed above. The films were produced using a single screw extruder, as discussed above, except 1 wt % chemical foaming agent (FZ 73s) was added at the feed hopper to produce a foamed film (Ex 12). Ex 12 foam sample, at a thickness of 20 mil, passed in the qualitative composting test after 10 weeks. The results are summarized in Table 12.
Ex 12 @ 20 mil foam sample disintegrated well in 20 weeks under OWS home composting conditions. Ex 12 completed disappeared in 26 weeks under home composting conditions (Table 13).
In general, degradation is followed by the determination of parameters such as DOC (dissolved organic carbon), CO2 production and oxygen uptake. There are three main methods for testing the biodegradation of a material: the Sturm method, respirometry method, and the radio-labeled 14C atom test method. The Sturm method precisely measures carbon dioxide production through a change in pressure. The respirometry test precisely measures the oxygen consumption over 60 days. Finally, the radio-labeled 14C atom test determines 14C conversion to 14CO2. All three methods can be used under aquatic or composting conditions if the right equipment is used.
Freshwater Modified Sturm Test (OECD 301 B) The amount of carbon dioxide (CO2) produced as a percentage of theoretical yield (based on total organic carbon analysis) is used as a basis for assessing whether the material biodegrades. CO2 is measured by way of a sodium hydroxide trap. The study is run for a minimum of 28 days and may be continued if the yield of CO2 is showing signs of increase towards the end of the 28-day period.
Biodegradation Test—O2 Consumption (OECD 301 F) may be used to monitor biodegradation of polymeric materials. OECD 301 F is an aquatic aerobic biodegradation test that determines the biodegradability of a material by measuring oxygen consumption. OECD 301 F is most often used for insoluble and volatile materials that are challenged by OECD 301 B testing. The purity or proportions of major components of the test material is important for calculating the Theoretical Oxygen Demand (ThOD). Like other OECD 301 test methods, the standard test duration for OECD 301 F is a minimum of 28 days and can measure ready or inherent biodegradability. A solution or suspension, of the test substance in a mineral medium is inoculated and incubated under aerobic conditions in the dark or in diffuse light. A reference compound (typically sodium acetate or sodium benzoate) is run in parallel to check the operation of the procedures.
There are three classifications of biodegradability: readily biodegradable, inherently biodegradable, and not biodegradable. A material is readily biodegradable if it reaches 60% of its theoretical oxygen demand within 28 days. Inherently biodegradable materials also reach the 60% level, but only after the 28-day window has passed. Normally, the test for materials that are readily biodegradable lasts for 28 days, while a prolonged test period may be used to classify materials as inherently biodegradable.
The OxiTop method is modified Sturm method to analyze biodegradation while reporting biodegradability as oxygen consumption, converting the pressure from the CO2 produced during the test to BOD, biological oxygen demand. OxiTop provides precise measurement in an easy to use format for aquatic biodegradation. Biological Oxygen Demand [BOD] was measured over time using an OxiTop@ Control OC 110 Respirometer system. This is accomplished by measuring the negative pressure that develops when oxygen is consumed in the closed bottle system. NaOH tablets are added to the system to collect the CO2 given off when O2 is consumed. The CO2 and NaOH react to form Na2CO3, which pulls CO2 out of the gas phase and causes a measurable negative pressure. The OxiTop measuring heads record this negative pressure value and relay the information wirelessly to a controller, which converts CO2 produced into BOD due to the 1:1 ratio. The measured biological oxygen demand can be compared to the theoretical oxygen demand of each test material to determine the percentage of biodegradation. The OxiTop can be used to screen materials for ready or inherent biodegradability.
Aquatic biodegradation rates of cellulose, cellulose acetate (CA) and CA blended with PEG400 were compared using the Oxitop method. Biodegradation refers to mineralization of a substance, or conversion to biomass, CO2 and water by the action of microbial metabolism.
The Test Substances included a cellulose positive control (PC) and cellulose acetate (DS 2.5), both added as powders. CA398-30 is a high-viscosity, high molecular weight cellulose acetate supplied as fine, dry, free-flowing powder. The powder's uniform particle size permits good plasticizer distribution during blending. The average particle size is about 200-250 microns, with a maximum particle size of about 500 microns. The CA resin (CA398-30) was added as the unmodified powder. The CA resin was also uniformly blended with plasticizer (PEG400 at 15%).
Aquatic biodegradation was evaluated essentially as described in OECD 301 F test method. Eastman sludge was used as the wastewater inoculum, and the wastewater sample was vacuum filtered to remove solid particles. The test was extended to 56 days from 28 days. The longer duration allows the both the identification of readily biodegradable materials (those which must pass in 28 days), as well as providing a screen for inherently biodegradable materials over a longer test duration. The data is initially collected as BOD measurements (mg/L O2), then the percent Biodegradation is calculated based on the elemental composition of the substance.
Marine biodegradation is essential when foam articles are accidentally discharged into waterway and finally floating in ocean. Foam alone is good for photodegradation already. Additional additives can be added to enhance the photodegradation especially when articles float in marine environment.
Accelerated UV testing indicates foam loses it molecular weight rapidly which may be beneficial for water or marine biodegradation if the article is accidentally released into waterways or ocean. The light weight foam article will float in water so that it will be exposed to UV easily during the day. The breakdown in molecular weight will enhance the disintegration rate of foam and thus marine biodegradation speed.
Ex 12 sample is cut into 4″×6″ which is exposed to UV fluorescent having peak radiance of 340 nm at 0.89 watt/m2 intensity for 8 hours @ 60° C. first. Then the UV is off for 4 h at 50° C. with condensed humidity on the vertical sample. The cycles will repeat until reach 168 h (14 cycles) which are equivalent to one-week UV exposure. Some sample will be removed for GPC molecular weight measurement. The rest will continue the UV exposure for another 168 h for two weeks. The original sample (0 week), sample exposed for 1 week, and sample exposed for two weeks are submitted for GPC molecular weight measurements. The normalized MW is the measured MW divided by the original MW which indicates the extent of molecular breakdown due to UV degradation. The original MW is 91,000.
Additional foams prepared from various compositions using a small extruder (D=1.5 inch L/D=24) are disclosed in Table 16. The compositions comprise TA (15 wt %, 20 wt %, 25 wt %) and three types of CBAs (HK40B, FZ 95, and FZ 73s) at two loadings (1 wt %, 2 wt %). All compositions contain 1% talc (ABT 1000), supplied by Barretts Minerals. All foams formed from the compositions are 20 mil thick and float in water which is indicative of a good weight reduction from the original density of about 1.30 g/cm3.
Ex 23 was used in large scale studies on a larger extruder (D=2.5 inch, L/D=30) to further optimize the loading levels (0.7 wt %, 1 wt %, 1.3 wt %) of the chemical foaming agent as shown in Table 17. Ex 12 showed similar results as Ex 23. The density of Ex 12 was found to be about 0.7 (about 50% weight reduction from 1.30). A film sample of Ex 12 was thermoformed into trays using vacuum.
Ex 34 in Table 15 is a beige color CA foam which already differentiates itself with the ubiquitous white PS foam. To further stand out, Bayferrox 6593 iron oxide, supplied by Lanxess, can be used to match the color of Kraft paper. Furthermore, the texture and touch of CA foam can be modified by any natural fiber such as hemp core fiber (hurd) as shown in Table 18, Ex 35. Hemp core fiber, 1 mm long, was supplied by Centralinfiber. The hemp fiber also improves the HDT of the foam about 14° C. @ 0.45 MPa load and 17° C. @1.86 MPa load. The HDT is determined by DMA under a specific tensile load at the temperature where 2% elongation of sample occurs.
The hemp fiber reinforced foam also demonstrates high Young's modulus in both machine direction (MD) and transverse direction (TD) for greater rigidity in stackability but lower elongation at break for easier tearing in home composting than its counterpart without fiber as shown in Table 19. Hemp fiber is expected to accelerate the overall degradation of cellulose acetate foams. Based on the results, cellulose acetate foams reinforced with hemp fiber are expected to provide to provide heat resistance and stackability properties that are better suited for hot food applications such as in foamed food containers. Thus, a fiber reinforced foam with higher HDT and stiffness has a performance advantage over the non-reinforced version.
bioCBA
Commercial CBAs usually use a low melting temperature polymer carrier such PS or PE so that it can be compounded at relatively low temperature with the active blowing agents such as sodium bicarbonate and citric acid so that the blowing agents will not be thermally decomposed prematurely. However, the polymer carrier is not biodegradable and could end up with microplastics in the marine environment. To develop a 100% biodegradable foam without remaining microplastics when the article is accidentally discharged into the ocean, a biodegradable chemical blowing agent is highly desired. Two bioCBAs were made by compounding all ingredients below 150° C. using a twin-screw extruder. Ex 36: 50 wt % BioPBS FD92PM/20 wt % sodium bicarbonate/30 wt % citric acid and Ex 37: 50 wt % CAPA 6500/20 wt % sodium bicarbonate/30 wt % citric acid. BioPBS FD92PM (Mitsubishi Chemical) and CAPA 6500. Two bioCBAs have similar weight loss up to 20% (from 100% to 80%) around 240° C. The commercial CBA FZ 73S has a different weight loss curve with 20% loss around 230° C. Two foam samples were made using two bio CBAs. The density of foam by using Ex 36 BioPBS FD92PM CBA is 0.6 g/cm3 while it is 0.4 g/cm3 by using Ex 37 CAPA 6500 CBA. These results indicate 100% biodegradable foam can be produced by utilizing a biodegradable CBA.
It is much more portable without major capital investments for extruding foam using a CBA. Injection molded foam articles can also be made using a CBA. However, this CBA technology is more suitable for high density foam. For low density foam production such as PS foam, a PBA should be used with a gas injection system.
Extrusion Process for Foams Made from a PBA
The cellulose acetate resin is dried at 60° C. for 4 hours. The resin is then fed into a single screw extruder with a CO2 super critical fluid injector. The extrusion temperature profile is shown in the table below. CO2 is injected directly into the melt. The foam is formed when the melt exits the die.
Table 21 shows the effect of the wt % of carbon dioxide on the density of the foam. As shown, the density of the foams can be adjusted by the amount of carbon dioxide injected. The higher the carbon dioxide loaded, the lower the density of the foam.
Cellulose acetate used was either CA398-30 having a melting point from 230-250° C., and a Tg of about 189° C. or CE41972 having a melting point from 240-260° C., and a Tg of about 180° C. Plasticizers were either TA (Eastman, food grade) or PEG400 (Dow Sentry Polyethylene Glycol 400).
Additives used were BHT; Irganox 1010 (pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate from BASF); DLTDP; Weston 705T phosphite (from SI Group), Doverphos S-9228T phosphite (from Dover Chemical), EPSO, and citric acid (from Sigma Aldrich).
Solutions were made containing 12% cellulose acetate in acetone. Plasticizer and additives were included in the solution as indicated. Films (˜15 mil) were cast from acetone into flat-bottom aluminum dishes, and solvent evaporation was controlled over 48 h by covering the pans. Film thickness was measured with a digital micrometer (Mitutoyo Digimatic Micrometer, MDC-1″ PX) with 0.05 mil resolution.
Films were cut into quarters, and the quarters of four different films were laid into a single aluminum dish. A second aluminum dish was stacked on top of the films, and the two aluminum dishes were clamped together with a clip. The aluminum dish assembly was placed in an oven set at 200° C. for one hour, then removed and allowed to cool to room temperature. The films were removed from the aluminum dish assembly, and the color was measured using a CR-400 Chroma Meter from Konica Minolta to determine L*, a*, and b*.
Cellulose acetate was compounded with plasticizer and optionally additives to make pellets. Specific formulations are listed in the tables below. Compounding was done using a Leistriz 18 mm twin screw extruder. The screw RPM was typically about 560, although it varied from 416 to 584 RPM. The torque ranged from 26.7 to 50%. The melt temperature ranged from 255-275° C. The melt pressure ranged from 412-580 psi. The SEI ranged from 0.147 to 0.326. The barrel has 9 zones, set in a gradient from about 64° C. to about 240° C. The material was extruded through a die set at 235-250° C.
Plaques were injection molded using a Toyo injection molding machine to form 4″×4″×125 mil plaques. The compounded pellets were first dried at 60-65° C. for 1-6 h before use. The barrel had 5 zones, which were set at 500-465° F. in most instances (460-450° F. for one set of plaques). The mold cooling was set at 120° F., or for some sets of plaques at 70° F. Two different cycle times were used for most sets of plaques; a “regular” cycle time of ˜39 seconds, as well as a “doubled” cycle time of about 78 seconds.
Color values reported herein are CIELAB L*, a*, and b* values measured following ASTM D 6290-98 and ASTM E308-99, using measurements from a CR-400 Chroma Meter from Konica Minolta. Unless stated otherwise, the measurements were performed on injection molded plaques having a thickness of 125 mils.
Formulations of CA398-30/PEG400 with various additives were injection molded into 125 mil plaques, and the b* was measured with a colorimeter. Plaques were made by 2 methods, using a normal cycle time during injection molding and by doubling the cycle time during injection molding (as discussed above). The data are presented in Tables 22 and 23 below.
A review of Tables 22 and 23 reveals that the presence of the acid scavenger (Vikoflex 7170) does not seem to have a large effect on color. Although not shown in the tables, it was observed that the Vikoflex sometimes resulted in increased haze in thicker parts. Also, the primary antioxidant alone (BHT or Irganox 1010) appears to have little effect on color, with some data showing it may have resulted in a slight increase in color. However, the presence of the secondary antioxidants provided a significant reduction in b*. Examples of CE41972 with 17 wt % PEG400 (Ex 45)
Formulations with various additives were initially screened by making solvent cast films (as described above). The results of screening indicated that the CE41972/PEG400 combination with no additives resulted in much higher color than either CE41972/TA or CA398-30/PEG400 formulations. Also, the addition of Vikoflex 7170 resulted in a further slight increase in b* and the primary antioxidant alone appeared to have little effect on b*. However, the secondary antioxidant alone (DLTDP or Weston 705T) resulted in significant reduction of b* and citric acid alone reduced b*, while the secondary antioxidant (DLTDP or Weston 705T) combined with citric acid reduced b* more than either alone, combining DLTDP and Weston 705T reduced b* more than either alone, and combining DLTDP and Weston 705T and citric acid reduced b* slightly more than when using only 2 of the 3.
Based on the screening results, formulations of CE41972/PEG400 with various additives were injection molded into 125 mil plaques, and the b* was measured with a colorimeter. The data are presented in Tables 24 and 25 below.
A review of Tables 24 and 25 reveals that the plaque results validate the screening results, and show that for the CE41972/PEG400 combination, the lowest color is achieved when both a phosphite antioxidant (Doverphos S-9228T or Weston 705T) and citric acid are included and that the color can be further improved slightly by adding DLTDP (an additional secondary antioxidant) to the phosphite antioxidant.
Formulations of CE41972/TA with various additives were injection molded into 125 mil plaques, and the b* was measured with a colorimeter for plaques made using regular and double cycle times (as discussed above). The data are presented in Tables 26 and 27 below.
A review of Table 26 reveals that not all antioxidant combinations result in reduction of b* in molded plaques. A combination of BHT and DLTDP did not reduce b*, whereas a combination of Irganox 1010 and Weston 705T did.
A review of Table 27 reveals that either of the secondary phosphite antioxidants Doverphos S-9228T or Weston 705T, when paired with the primary antioxidant Irganox 1010, resulted in a large decrease in b*. Surprisingly, in contrast to CA/PEG400 (Table 23), the secondary antioxidants by themselves did not reduce color quite as much.
A series of plaques were made with either PEG400 or TA as plasticizer, including either a secondary antioxidant only, or a primary and secondary antioxidant combined, by injection molding plaques using regular and double cycle times (as described above). The results are presented in Table 28.
A review of Table 28 reveals that there was a difference based on which plasticizer was used. Both combinations (CA398-30/PEG400 and CA398-30/TA) had significantly reduced color when a secondary antioxidant was added. However, addition of Irganox 1010 had no benefit when using PEG400 (Ex 47-4), whereas addition of Irganox 1010 resulted in some additional reduction in color when using TA (Ex 47-8).
For each of the examples, CA398-30 was compounded with TA, (1 wt %) EPSO, and one or more biopolymers and then extruded into a film or injection molded into a plaque. The biopolymers used were PHB(6)Hx and CAPA 6500.
The film or plaque was either made by a two-step process or a one-step process. For the two-step process, the material is pre-compounded on a twin-screw extruder and then extruded on a single screw extruder or molded in an injection molding machine. For the one step process, the materials were made by physical blending pellets and then completing the extrusion on a single screw extruder. All materials were dried prior to molding and extrusion at a temperature of 60° C. in a desiccant drying system.
Ex 50-53 films were prepared using the two-step process, where the material was pre-compounded on a Leistritz 18 mm twin screw extruder at 180 to 200° C. at a rate of 15 lbs/hr. at a screw speed of 500 rpm. The material was then extruded on a 1.5″ Killion extruder having a L/D of 24:1 and using a general-purpose screw with a maddock mixing section. The material was processed at a profile of 200° C. to 215° C. on the barrel and 225 to 230° C. on the die to make a 0.020 inch (20 mil or about 0.5 mm) film. Ex 56 and 57 were made the same way, except a die was used to make a 0.030 inch (30 mil or about 0.76 mm) film.
Ex 54 film was prepared using the one-step process, where the material was physically blended and then extruded on a 1.5″ Killion extruder having a L/D of 24:1 and using a general-purpose screw with a maddock mixing section. The material was processed at a profile of 200° C. to 215° C. on the barrel and 225 to 230° C. on the die to make a 0.020 inch (20 mil or about 0.5 mm) film.
Ex 55 plaques were prepared using the two-step process and injection molding, where the material was pre-compounded on a Leistritz 18 mm twin screw extruder at 180 to 200° C. at a rate of 15 lbs/hr. at a screw speed of 500 rpms. The material was then molded on a 90-ton Toyo Injection molding machine. The material was processed at a profile of 210° C. on the barrel and a mold temperature of 20° C. on the mold to make a 0.060 inch (60 mil or about 1.5 mm) plaque.
Film or plaque samples were subject to pilot-scale aerobic composting tests in a similar manner to the tests conducted as described for Ex 1 and 2. The specific formulations used for each example and the disintegration test results are shown below in Table 29.
A review of Table 29 reveals that the lower amount (10 wt %) of PHB(6)Hx (compared to a higher amount at 20 wt %) resulted in higher disintegration for higher levels of TA (27 wt %). The combination of the two biopolymers resulted in good disintegration after 12 weeks for 17 wt % TA at both 20 and 30 mils thickness and greater than 50% disintegration at 60 mils thickness. Also, 20 wt % CAPA 6500 alone resulted in good disintegration after 12 weeks for 17 wt % TA at 30 mils thickness.
In the following examples, different grades of cellulose diacetate (CDA) were compared for use in compositions for forming extruded articles, including extruded foams using CO2 as a physical blowing agent. More particularly, stabilized biodegradable CDAs of the present invention, identified herein from time to time as CE41972 in powder form or in flake form as CA-394-60S, were compared to a second control CA identified herein from time to time as CA-398-30.
A number of separate foamable biodegradable compositions were formed using each CA, with each composition including Triacetin (TA) as plasticizer at 15 and 20 wt % loadings and epoxidized soybean oil (Vikoflex 7170, Arkema) in an amount of 1.0 wt. %. Talc (ABT-1000) was used as the nucleating agent at loadings of 0.75 to 3.0 wt % (added during foam extrusion at feed throat of extruder). Pellets for foamable composition were prepared by compounding using a co-rotating twin-screw extruder.
Foamable compositions and foam sheets of varying thicknesses were also made from the foamable compositions using a tandem extruder setup wherein the CA composition was melted and a physical blowing agent (CO2) and the talc were mixed in a twin screw extruder (ZE 30) and then melt was transferred to a single screw extruder (KE 60). An annular die was used to extrude a foam sheet tube and the tube stretched and cut open over a calibrator cylinder to form the sheet.
Foamable compositions in pellet form were then characterized and compared using number of different parameters. Complex viscosity data was collected at 200, 220, and 240° C. for compositions of CA-398-30 and CA-394-60S with 1.0% Vikoflex 7170 (as acid scavenger) and 15% Triacetin (as plasticizer).
Complex viscosity (in Poise) was determined according to ASTM D-4440 at shear rates starting a 1 sec−1 and then at increasing shear rate up to 400 sec−1. The results are set forth in Table 30 below.
A review of Table 30 reveals that the composition made using the CA-394-60S (60S Composition) has sheer-thinning properties that exceed the sheer-thinning properties of the composition made using the CA-398-30 (30 Composition). The sheer-thinning property can be seen by the difference in viscosity measured at 1 rad/s compared to higher sheer, e.g., 100 or 400 rad/s. The 60S Composition has a higher delta at 1 rad/s-100 rad/s (ΔVisc-100) and at 1 rad/s-400 rad/s (ΔVisc-400) compared to the 30 Composition at each of the temperatures in Table 30. The ΔVisc-100 was more than 3% higher at 220° C. and more than 8% higher at 240° C. for the 60S Composition. The ΔVisc-400 was more than 1% higher at 220° C. and more than 4% higher at 240° C. for the 60S Composition.
In embodiments, the biodegradable melt-stable composition has a ΔVisc-100 percent decrease at 220° C. of at least 84%, or at least 85%, or at least 86%, or at least 87%. In embodiments, the biodegradable melt-stable composition has a ΔVisc-100 percent decrease at 240° C. of at least 68%, or at least 69%, or at least 70%, or at least 71%, or at least 72%, or at least 73%, or at least 74%, or at least 75%. In embodiments, the biodegradable melt-stable composition has a ΔVisc-400 percent decrease at 220° C. of at least 94%, or at least 95%. In embodiments, the biodegradable melt-stable composition has a ΔVisc-400 percent decrease at 240° C. of at least 85%, or at least 86%, or at least 87%, or at least 88%, or at least 89%.
In embodiments, the biodegradable melt-stable composition has a ΔVisc-100 percent decrease at 220° C. that is at least 1% greater, or at least 2% greater, or at least 3% greater, than a similar composition that has a CA having an HIV less than 0.9 and an M/S ratio less than 1.35. In embodiments, the biodegradable melt-stable composition has a ΔVisc-100 percent decrease at 240° C. that is at least 3% greater, or at least 4% greater, or at least 5% greater, or at least 6% greater, or at least 7% greater, or at least 8% greater, than a similar composition that has a CA having an HIV less than 0.9 and an M/S ratio less than 1.35. In further embodiments, in addition to having a greater ΔVisc-100 percent decrease (as discussed above), the biodegradable melt-stable composition has better (or higher) molecular weight retention (e.g., at least 1%, or at least 2%, or at least 3% or at least 4% higher Mn retention) after heating for 20 minutes at 220° C., or 240° C., compared to a similar composition that has a CA having an HIV less than 0.9 and an M/S ratio less than 1.35.
Foamable compositions were also characterized and compared for molecular weight retention (a measure of melt stability and melt strength retention) using a protocol wherein pellets were melted and analyzed for molecular weight data (Mn, Mw and PD) using GPC with NMP as solvent and polystyrene equivalent Mn according to ASTM D6474; subjected to rheological melt processing conditions (temperature is raised 220 C and held for 20 minutes; and then re-analyzed. The results are set forth in Table 31 below.
The foam sheet samples described above were characterized and compared using a number of different parameters. The density of the extruded sheet was measured using an analytical balance where the sample was immersed in water and Archimedes principle was used to measure the volume. The method is described in DIN EN ISO 1183-1, ISO 2781. A minimum 3 samples were measured and weight of each sample was between 1-5 gm. The results are set forth in Table 32 below.
Foam morphology and average cell size was measured for come sample foam each from CA-3980-30-based compositions and CA-394-60S-based compositions using vision assistant—LabVIEW software via automated algorithms. The results are set forth in Table 33 below.
Photomicrographs of machine and traverse cross-sections of these foams were also generated (70×, 5.0 kV, SE detector, 3.95 mm view field) to characterize foam morphology and cell size and are provided in the
Foam compression deflection was measured using the procedure described in standard ASTM D3575 with 16 kPa preload and test speed of 12.5 mm/min. A ˜25 mm high stack of extruded films was used with a 50 mm×50 mm dimension. The results are set forth in Table 34 below.
Foam thermal conductivity was measured using a Transient-hot-bridge method as described in standard DIN EN 993-15:2005 using Linseis THB1 instrument. The results are set forth in Table 35 below.
Compositions of the present invention were also prepared and analyzed as set forth here.
Cellulose acetate used was either CA-398-30 (DS=2.5; mp 230-250° C., Tg 188-192° C.) or a modified fiber ester (CA-394-60S) (DS=2.5; mp 230-250° C. Tg 188-192° C.). Plasticizers were either triacetin (Eastman, food grade) or DEP (Sigma Aldrich).
Additives used were malic acid (Sigma Aldrich), tartaric acid (Sigma Aldrich), DL-Lactic acid (Sigma Aldrich), and citric acid (Sigma Aldrich).
Round disks of formulated materials were prepared by combining 15.3 g of ester and 5.0 mL of DEP. The formulated powder samples were subjected to heat on a plate at 180° C. for 10 min to bring the powder into the melt phase and pressed under high temperature and pressure to simulate compounding and induce color formation. Samples are pressed in a Dake press. Dake plates were heated to 180° C. and once internal thermocouple reached 160° C. samples were pressed under 150-250 psi for 10 minutes. After pressure was released, samples were cooled under water for 10 minutes. Disks are rinsed in acetone to smooth surfaces before measuring the color. Initial samples were pressed at heat plates set to 160° C. and 10 minute timer would begin at 140° C. Because of unmelt and lack of color formation, the temperature was increased.
The disks once removed from the heat plate create a 155-mil disk. The color was measured using a UltraScan Vis colorimeter by Hunter Lab to measure the resulting L*, a*, and b*.
Cellulose acetate was compounded with plasticizer and additives to make pellets; formulations are listed in the tables below. Compounding was done using a Leistritz 18 mm twin screw extruder. The screw RPM was typically about 507, although it varied from 490 to 600 RPM. The torque ranged from 14 to 22%. The melt temperature ranged from 242-252° C. The melt pressure ranged from 288-400 psi. The SEI ranged from 0.15 to 0.34. The barrel has 9 zones, set in a gradient from about 80° C. to about 240° C. The material was extruded through a die set at 235-250° C.
Plaques were injection molded using a Boy injection molding machine to form 1.5″×1.5″×125 mil plaques or using the 110 Ton TOYO M1 to form 4″×4″×0.125″. The compounded pellets were first dried at 60-65° C. for 3-6 hours before using. The barrel has 5 zones, which were set at 400-465° F. in most instances (450-460° F. for one set of plaques). The mold cooling was set at 120° F.
Plaques (125 mil) were measured using a HunterLab UltraScan Vis colorimeter to determine L*, a*, and b*.
A weighed amount of sample is heat treated at an initial heat temperature of 50° C. and held for 3 minutes. The temperature is ramped to 20 DPM until 250° C. is reached and held for 3 minutes. Post treatment the sample is added to acetone so that the solution has a concentration of 0.50 g/dL. The relative viscosity is measured at 30° C. using a Viscotek Y501C automated viscometer and the intrinsic viscosity is calculated using the Solomon-Gatesman equation with units of dL/g. Data regarding the characterization of the compositions was generated as set forth in Tables 36 through 49 below.
Blanks indicate samples were unable to mold because of molecular weight loss/low viscosity
The foamable compositions were also characterized for melt extensivity. Melt extensivity is important for the foaming process, where the polymer melt undergoes a high degree of deformation. Low melt extensivity can lead to cell wall rupture or collapse, leading to cell coalescence, roughening of cell structure, and reduce mechanical properties. Measurable parameters such as Sentmanet extensional rheology (SER), Hencky strain and stress/strain ratio can be useful in evaluating melt extensivity. SER measures the elongational melt behavior of a material. Hencky strain at break and stretch ratio from this test describes how much a material can stretch before it ultimately fails (tears or snaps).
To evaluate melt extensivity, foamable compositions were formed and extruded into pellets. Extruded pellets were dried at 60° C. under vacuum for 24 hours. GPC data regarding the pellets is set forth below in Table 48:
The above pellets were then placed between two aluminum sheets in a 4 in by 4 in, 10 mil frame and compression molded at 420 F to form a film.
For each SER test, a 18 mm×6.35 mm strip was cut from a dried sample of film. The sample strip was then placed on the two windup drums of TA ARES-G2 rheometer. The drums rotated outwards at Hencky rate of 0.1/s causing the sample to stretch. Torque generated by the resistance of the sample was recorded as a functional of Hencky strain. The film was stretched until ultimate failure and the Hencky strain at break is recorded in Table 49 below. Stretch ratio was calculated using the equation below:
where ε is the hencky strain, I and L is the initial and final length, and A is the stretch ratio of sample.
Regarding the foamable compositions of the present invention, a number of conclusions may be postulated from the generated data. Compositions of the present invention from CA-394-60S maintain both Mn and Mw through compounding and melt stability testing at 220° C. for 20 minutes and are more stable upon thermal processing as compared to control compositions from CA-398-30. This molecular weight maintenance upon compounding and corresponding higher zero shear compared to control compositions from CA-398-30 can translate to improved melt strength properties in sheet extruded films. Compositions of the present invention, upon high shear, result in a measured viscosity which is advantageous for thermal processing into articles. Compositions of the present invention have desirable melt strength in films, maintain melt strength with additives, and maintain good flow properties flow, for example as demonstrated in a spiral flow mold test described herein. The higher melt extensivity of the compositions of the present invention was afforded by its ability to maintain molecular weight in thermal processing as shown in Table 36. The Mn, and MW of the compositions of the present invention was shown to be 10% and 21% higher than that of control compositions with CA-398-30.
Regarding the foams of the present invention, a number of conclusions may be postulated from the generated data. Foams of the present invention achieve lower density and increased stiffness than the control foam (made with CA-398-30). Foams of the present invention have ˜10% lower cell size than the control foams made using CA-398-30 with similar formulations and processing conditions. The smaller cell size may be commercially beneficial as it can lead to lower density, stiffer foam and an increase in thermal insulation (or reduction in thermal conductivity). Foams of the present invention (made with CA-394-60S) also require ˜30% higher stress to achieve at 25% compression strain than the control foam (made with CA-398-30). A rigid foam may be commercially beneficial as it allows for use of reduced thicknesses to achieve article rigidity specifications. Foams of the present invention (made with CA-394-60S) are also less thermally conductive than the control foam (made with CA-398-30). A thermally insulating foam may be commercially beneficial in food service, particularly in the manufacture of foam articles for containing foods for which temperature maintenance in desired. Overall, the foams of the present invention perform better than the control.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2022/037528 | 7/19/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63203353 | Jul 2021 | US |
