Patent Application
20150112000
1. Field of the Disclosed and Claimed Inventive Concepts
The presently disclosed and claimed inventive concept(s) relates generally to a method for making a particulate product comprising a nonionic synthetic associative thickener (NSAT) rheology modifier and a dissolution promotion water soluble additive, and incorporation of the particulate product into waterborne paint formulas.
2. Background and Applicable Aspects of the Presently Disclosed and Claimed Inventive Concept(s)
Nonionic synthetic associative thickener (NSAT) rheology modifiers such as hydrophobically-modified ethoxylated urethane (HEUR), hydrophobically-modified polyethylene glycol (HMPEG), and hydrophobically-modified polyacetal-polyether (HMPAPE) have enjoyed widespread use in waterborne paint formulas due to their ability to provide superior rheological characteristics such as spatter and sag resistance, leveling, and brush flow. These materials are usually manufactured at the production facility, added to water as molten solids to dissolve and then shipped to customers as aqueous solutions. The active solid contents of these solutions generally range from 17 to 30 wt %.
Products delivered in this form suffer a number of drawbacks and limitations. The high water contents of these products mean that customers are paying to ship substantial quantities of water, which wastes fuel and has a negative environmental impact. In addition to excess shipping cost, these products are often packaged in drums or totes, which increases the packaging cost of the active product. Disposal or recycling of the packaging materials has both negative cost and environmental consequences.
The manufacture of waterborne coatings typically requires combining a large number of ingredients. Coatings manufacturing processes have evolved over many years to avoid degrading raw materials and flocculating particles. Water represents a key ingredient which must be added at appropriate points in the manufacturing process. This is especially true in “low” volatile organic compound (VOC) formulas where the amount of water is limited. Since the use of water to deliver NSAT rheology modifiers reduces the amount of available “free” water, it limits both product compositions and the manufacturer's process design flexibility. Furthermore when making final viscosity adjustments to achieve the desired paint viscosity, it is undesirable to add water to the paint since this effectively changes the balance of ingredients by dilution.
The hydrophobic associative nature of these products often necessitates the use of viscosity suppressants which represent a significant cost of the final product. The sole function of these additives is to reduce the viscosity of the product to permit it to be more readily handled in the coating manufacturing plant. Unfortunately, not only do these additives not contribute to the performance of the formulated paint, but they can deleteriously impact key paint properties. The viscosity suppressants often contain VOCs which are undesirable from both health and environmental standpoints.
Due to their propensity to phase separate, insoluble NSAT rheology modifier byproducts sometimes present a difficult challenge from both product stability and paint performance perspectives.
Aqueous delivery imposes environmental temperature storage restrictions as well as requires additional storage space to accommodate the product in liquid form. In the production of these materials tanks are required to both prepare and provide intermediate solution storage.
The aqueous delivery vehicle imposes constraints on the production of multifunctional products since all additives must be compatible to avoid separation.
The presently disclosed and claimed inventive concept(s) relates to a method for making particulate product comprising a nonionic synthetic associative thickener (NSAT) rheology modifier and a dissolution promotion water soluble additive. The NSAT rheology modifier used in the presently disclosed and claimed inventive concept(s) is selected from the group consisting of hydrophobically-modified ethoxylated urethane (HEUR), hydrophobically-modified polyethylene glycol (HMPEG), and hydrophobically-modified polyacetal-polyether (HMPAPE).
The dissolution promotion water soluble additive has a molecular weight (Mw) less than about 2000 Daltons. In one non-limiting embodiment, the dissolution promotion water soluble additive can be a surfactant or a cyclodextrin. Examples of surfactants can include, but are not limited to, isodecyl ethoxylate (Genapol™ ID 060 surfactant from Clariant International Ltd.). Examples of cyclodextrins can include, but are not limited to, α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin. In one non-limiting embodiment, the cyclodextrin is methyl-β-cyclodextrin. The type and optimal concentration of the dissolution promotion water soluble additive will depend upon the chemical nature of the NSAT rheology modifier, including the hydrophobe as well as its concentration and polymer substitution level.
In another non-limiting embodiment, the dissolution promotion water soluble additive can be a sugar. While not wishing to be bound by theory, it is believed that the sugar interrupts the intermolecular polymer chain hydrogen bonding of the NSAT polymer backbone. Examples of sugars used in the presently disclosed and claimed inventive concept(s) can include, but are not limited to, sucrose, fructose, glucose and sorbitol. These additives are understood to be added in a fashion that they can be intimately incorporated into the particles. A preferred means involves mixing the additive into the melt prior to production of the particles.
The particulate product in the presently disclosed and claimed inventive concept(s) permits a dramatic reduction in shipping costs, storage volume, as well as the use of lower cost, more environmentally friendly packaging materials. The particulate product can be added either to the “let-down” or “grind” stages of paint making. Especially for particles added to the “let-down” stage, there is a preferred particle size range for the powder.
The particle size of the particulate product used in the “let down” stage of paint making can be measured according to ASTM C136-06 Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates. In one non-limiting embodiment, less than about 5% particles retained on 1.18 mm sieve (No.16) can be used. In another non-limiting embodiment, less than about 5% particles retained on 300 micron sieve (No. 50) sieve can be used. In yet another non-limiting embodiment, less than about 5% particles retained on 150 micron sieve (No. 100) can be used.
Blends with rheology modifiers, for example but by no way of limitation, NSATs and cellulose ethers, can be produced to tailor product rheology to specific customer paint formulations. Such blends may contain dissolution promotion water soluble additives previously mentioned. NSAT polymer architectures are often tailored to address high, middle, or low shear rheology needs. Blending of products represents a means of using a small base set of rheology modifiers to produce a broad range of custom products. Examples of cellulose ethers can include, but are not limited to, hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), methyl cellulose (MC), methylhydroxyethyl cellulose (MHEC), ethylhydroxyethyl cellulose (EHEC), methylhydroxylpropyl cellulose (MHPC), as well as hydrophobically-modified derivatives of the aforementioned cellulose ethers.
The blends can be prepared in the molten phase prior to particle formation or as dry blends of individual powder components. In addition to tailoring rheology through blending, other functional ingredients utilized in paint manufacturing can also be incorporated into the NSAT rheology modifier particles (with or without dissolution promotion water soluble additives) to simplify paint manufacturing by reducing the number of materials which must be added during paint manufacturing. Examples of such functional ingredients can include, but are not limited to, dispersants, wetting agents, surfactants, biocides, antifoam, and coalescents.
The particulate product in the presently disclosed and claimed inventive concept(s) further comprises a coating composition. The coating composition includes a hydrophobic polymer, hydrophilic polymer and an amphiphilic polymer.
A method for making a particulate product comprising a nonionic synthetic associative thickener (NSAT) rheology modifier and a dissolution promotion water soluble additive, comprises the steps of: a) obtaining the NSAT rheology modifier and the dissolution promotion water soluble additive; b) melting the NSAT rheology modifier and the dissolution promotion water soluble additive; c) mixing the molten NSAT rheology modifier and the dissolution promotion water soluble additive and d) producing the particulate product from step c).
The particulate product can be prepared by using equipment in a number of ways which are known to those skilled in the art of polymer processing. Examples of suitable equipment can include, but are not limited to, spray dryers, disc pastillators, drum flakers, and grinders. Larger particles can be further reduced in size using appropriate mills Since poly(ethylene glycol) based polymers melt at relatively low temperatures, cryogenic grinding can be beneficial. In addition, particles can be produced by solvent precipitation processes into nonsolvents. The specific process used will depend upon the synthetic process for the production of the NSAT rheology modifier as well as particle size requirements.
It is also possible to coat the NSAT rheology modifier particles with a dissolution promotion water soluble additive, such as a sugar, surfactant or cyclodextrin, or an additional rheology modifier, such as cellulose ether, or a functional ingredient. Additionally, it is also possible to coat the NSAT rheology modifier particles with hydrophobic, hydrophilic, and/or amphiphilic polymers, if desired. This coating step can be accomplished by any means commonly used, such as spray drying and the like.
The particulate product in the presently disclosed and claimed inventive concept(s) can be incorporated into an aqueous system. In one non-limiting embodiment, a method for incorporating a particulate product comprising a nonionic synthetic associative thickener (NSAT) rheology modifier and a dissolution promotion water soluble additive into an aqueous system comprising a water-insoluble polymer, comprises: a) obtaining the particulate product obtained from the method described previously; and b) mixing the particulate product and the aqueous system until the particulate product dissolves,
In another non-limiting embodiment, a method for incorporating a particulate product comprising a nonionic synthetic associative thickener (NSAT) rheology modifier and a dissolution promotion water soluble additive into an aqueous system comprising a water-insoluble polymer, comprises: a) obtaining the particulate product obtained from the method described previously; b) adding the particulate product to the aqueous system in the absence of a water-insoluble polymer to obtain a mixture; c) grinding the mixture; and d) adding a water-insoluble polymer to the mixture until the particulate product dissolves.
In one non-limiting embodiment, the water-insoluble polymer can be latex used to make a waterborne paint. Generally, waterborne paints (latex paints) are the paints in which resin binders are dispersed in solvents in form of small insoluble resin particles (colloids and coarse dispersions). The resin binders can include, but are not limited to, polyvinyl acetate, styrene-butadiene copolymer, acrylics, polystyrene, and alkyds.
The following examples illustrate the presently disclosed and claimed inventive concept(s), parts and percentages being by weight, unless otherwise indicated. Each example is provided by way of explanation of the presently disclosed and claimed inventive concept(s), not limitation of the presently disclosed and claimed inventive concept(s). In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the presently disclosed and claimed inventive concept(s) without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used on another embodiment to yield a still further embodiment. Thus, it is intended that the presently disclosed and claimed inventive concept(s) covers such modifications and variations as come within the scope of the appended claims and their equivalents.
C16-capped poly(acetal-polyether) (C16-HMPAPE) was made as follows. To an Abbe ribbon blender were added polyethylene glycol [PEG-8000, MW˜8000 (1250 g)] and sodium hydroxide (37 g). After sealing the reactor, the mixture was heated at about 80° C. for about one hour. Then dibromomethane (18.5 g) was added to the PEG-8000/NaOH mixture and the resulting reaction mixture was heated at about 80° C. for about 4 hours to form PEG-8000/methylene copolymer.
To the PEG-8000/methylene copolymer at about 80° C. was added 1-bromohexadecane (65 g) and the resulting reaction mixture was heated at about 120° C. for about 2 hours. Following this, the reactor was opened and the molten reaction mixture was poured into a plastic tray. Upon cooling to room temperature, the reaction mixture was solidified. The crude reaction mixture was soluble in water (2% solution BF viscosity at 30 rpm=410 cps).
This solid C16-HMPAPE was cryogenically ground using a Cryomill: SPEC Freezer Mill. Small quantities (˜4 g) of solid materials were milled in liquid nitrogen for about 10 minutes to form a powder. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm), which resulted in all particles less than 1.18 mm.
A C12-HMPAPE was made according to Example 1 using 1-bromododecane (70 g) as the capping agent. The solid mixture was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for about 30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm), which resulted in all particles less than 1.18 mm.
A C12/C16 mixed hydrophobe end-capped PAPE (C12/C16-HMPAPE) was made according to Example 1 using 1-bromododecane (20 g) and 1-bromohexadecane (50 g) as the capping agents. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
The XLS-530 polymer was obtained by evaporation of water from Aquaflow® XLS-530 (available from Ashland Inc.) followed by dissolution in toluene at 2× weight of the solid. This material was further isolated by precipitation (in 5× volume of hexane), filtration, and drying. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid C16-HMPAPE (75 g) obtained from Example 1 and sucrose (25 g) was heated at about 80° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid C16-HMPAPE (50 g) obtained from Example 1 and sucrose (50 g) was heated at about 80° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid C16-HMPAPE (49.4 g) obtained from Example 1 and β-Cyclodextrin (β-CD) (1 g) was heated at about 100° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
Example 8—Methyl-β-Cyclodextrin+C16-HMPAPE (2%/98%)
A mixture of solid C16-HMPAPE (29 g) obtained from Example 1 and Methyl-β-Cyclodextrin (Methy-β-CD) solution (1 g, 50% aqueous solution) was heated at about 100° C. with stirring under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1 7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid C12-HMPAPE (75 g) obtained from Example 2 and sucrose (25 g) was heated at about 80° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid C12-HMPAPE (50 g) obtained from Example 2 and sucrose (50 g) was heated at about 80° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid of C12/C16-HMPAPE (50 g) obtained from Example 3 and glucose (50 g) was heated at about 70° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of C12/C16-HMPAPE (75 g) obtained from Example 3 and corn oil (25 g) was heated at about 70° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid polyetherpolyacetal of XLS-530 Polymer (50 g) obtained from Example 4 and sucrose (50 g) was heated at about 80° C. with stiffing under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of solid Rheolate® 208 (30 g, available from Elementis Specialties, Inc.) and Sucrose (30 g) was heated at about 130° C. with stirring under N2 atmosphere for about one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A 70 wt %/30 wt % mixture of the solid C16-HMPAPE of Example 1 and Natrosol® Plus 330 hydrophobically modified HEC (available from Ashland Inc.) was melt blended at about 120° C. in an Aaron mixer under N2 atmosphere for about one hour. Cooling to room temperature yielded a solid. This solid was cryogenically ground using a Cryomill: SPEC Freezer Mill. Small quantities (˜4 g) of solid materials were milled in liquid nitrogen for about 10 minutes to form a powder. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
A mixture of the product of Example 15 (50 g) and Sucrose (50 g) was heated at about 130° C. with stiffing under N2 atmosphere for one hour yielding a solid. This solid was ground in a “Mr. Coffee® IDS55” by pulsing the cutter blade for ˜30 seconds. The ground material was passed through stacked ASTM E-11 sieves: #12 (1.7 mm) and #16 (1.18 mm) which resulted in all particles less than 1.18 mm.
To illustrate improvements in dissolution characteristics arising from the incorporation of various additives, the samples from the preceding Examples were subjected to aqueous and paint dissolution testing.
The aqueous dissolution of rheology modifier was monitored using an anchor blade coupled with HAAKE viscometer. The dissolution was carried out in an 8 oz jar containing 200 grams of 100 mM of pH 8.0 Tris buffer. 2.0 grams of active powder rheology modifiers (with and without additives) from the above Examples were added dry to the jar which was mixing at 600 rpm. The mixing was carried out for about 45 minutes. Torque data was collected as a function of time which is analogous to dissolution as a function of time, as torque is related to the viscosity builds up of the solution which is dependent on the dissolution of the rheology modifier.
The paint dissolution of the rheology modifier was monitored using a marine propeller blade coupled with HAAKE viscometer. The dissolution was carried out in an 8 oz jar containing 245 grams of 45.5 PVC paint based on Rhoplex™ SG-10M (formulation is shown in Table 2).
0.6 grams of active powder rheology modifier (with and without additives) from the above Examples were added dry to the jar which was mixing at 600 rpm. The mixing was carried out for about 45 minutes. Torque data was collected as a function of time which is analogous to dissolution as a function of time, as torque is related to the viscosity builds up of the solution which is dependent on the dissolution of the rheology modifier. The comparison of dissolution characteristics of C16-HMPAPE powders in paint with and without additive is shown in
A sample of Example 2 powder was added (0.56 wt %) to the “Grind Phase” of the paint making process following addition of water. The paint formula (46 PVC, acrylic pastel base) used is shown below in Table 4. The grind was prepared using a Cowles mixing blade and a Dispermat mixer.
The C12-HMPAPE powder of Example 2 was dissolved rapidly. The final paint had a Stormer viscosity of 100 KU and ICI viscosity of 1.85 P.
While the invention has been described with respect to specific embodiments, it should be understood that the invention should not be limited thereto and that many variations and modifications are possible without departing from the spirit and scope of the invention.
It is, of course, not possible to describe every conceivable combination of the components or methodologies for purpose of describing the disclosed information, but one of ordinary skill in the art can recognize that many further combinations and permutations of the disclosed information are possible. Accordingly, the disclosed information is intended to embrace all such alternations, modifications and variations that fall within the spirit and scope of the appended claims.
The presently disclosed and claimed inventive concept(s) is a continuation of U.S. patent application Ser. No. 13/559,836, filed on Jul. 27, 2012, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/512,640, filed on Jul. 28, 2011, the entire contents of both of which are herein incorporated by reference in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61512640 | Jul 2011 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13559836 | Jul 2012 | US |
| Child | 14580550 | US |
