Plastic waste has escalated to an environmental crisis. Abandoned plastics in the ocean are expected to exceed fish (by weight) before 2050. Despite the increasing regulatory effort, plastics recycling rates remain low. Thus, technological developments that provide a more circular economy of plastics and/or provide alternative, bioderived raw materials for plastics manufacturing are urgently needed.
An aspect of the present disclosure is a composition that includes
where R includes a reactive end group, R1 includes a first bridging group, 1≤x≤100, and 1≤y≤100. In some embodiments of the present disclosure, R may include at least one of
and the symbol represents a covalent bond.
In some embodiments of the present disclosure, R1 may include at least one of
R2 may include a second bridging group, and 1≤u≤100.
In some embodiments of the present disclosure, R2 may include at least one of
In some embodiments of the present disclosure, R1 is
In some embodiments of the present disclosure, the composition may further include
where 1≤m≤100, and 1≤n≤100.
In some embodiments of the present disclosure, the composition may include at least one of,
In some embodiments of the present disclosure, the composition may have a tensile strength between about 20 MPa and about 100 MPa. In some embodiments of the present disclosure, the composition may have a modulus between about 0.5 GPa and about 3.0 GPa. In some embodiments of the present disclosure, the composition may have an elongation at break between about 0.1% and about 100%. In some embodiments of the present disclosure, the composition may have a glass transition temperature between about 0° C. and about 250° C.
An aspect of the present disclosure is a method that includes reacting a first functionalized intermediate with a second functionalized intermediate to form a product, where the first functionalized intermediate includes
the second functionalized intermediate includes
the product includes,
R includes a reactive end group, R1 includes a first bridging group, 1≤x≤100, and 1≤y≤100.
In some embodiments of the present disclosure, may further include, prior to the reacting, in a first mixture that includes a deconstruction product and a functionalized reactant, functionalizing the deconstruction product, where the deconstruction product includes
the functionalized intermediate includes at least one of
and the functionalizing produces the first functionalized intermediate including
and the second functionalized intermediate including
In some embodiments of the present disclosure, the reacting may be performed using a second mixture of the first functionalized intermediate and the second functionalized intermediate, and the first functionalized intermediate and the second functionalized intermediate may be at a molar ratio between about 1:2 and about 1:1. In some embodiments of the present disclosure, the second mixture may have a viscosity between about 800 cP and 1200 cP when measured at a temperature of about 25° C. In some embodiments of the present disclosure, the reacting may be performed at a temperature between 20° C. and 150° C.
In some embodiments of the present disclosure, the reacting may be photoinitiated at a wavelength between 254 nm and 500 nm. In some embodiments of the present disclosure, the reacting may be photoinitiated using at least one of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate (TPO-L), and/or phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (BAPO). In some embodiments of the present disclosure, the method may further include, prior to the functionalizing, deconstructing a plastic, where the deconstructing results in the forming of the deconstruction product. In some embodiments of the present disclosure, the plastic may include at least one of polyethylene terephthalate, glycol modified polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, and/or polyethylene 2,5-furandicarboxylate.
Some embodiments of the present disclosure are illustrated in the referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than limiting.
The present disclosure may address one or more of the problems and deficiencies of the prior art discussed above. However, it is contemplated that some embodiments as disclosed herein may prove useful in addressing other problems and deficiencies in a number of technical areas. Therefore, the embodiments described herein should not necessarily be construed as limited to addressing any of the particular problems or deficiencies discussed herein.
References in the specification to “one embodiment”, “an embodiment”, “an example embodiment”, “some embodiments”, etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
As used herein the term “substantially” is used to indicate that exact values are not necessarily attainable. By way of example, one of ordinary skill in the art will understand that in some chemical reactions 100% conversion of a reactant is possible, yet unlikely. Most of a reactant may be converted to a product and conversion of the reactant may asymptotically approach 100% conversion. So, although from a practical perspective 100% of the reactant is converted, from a technical perspective, a small and sometimes difficult to define amount remains. For this example of a chemical reactant, that amount may be relatively easily defined by the detection limits of the instrument used to test for it. However, in many cases, this amount may not be easily defined, hence the use of the term “substantially”. In some embodiments of the present invention, the term “substantially” is defined as approaching a specific numeric value or target to within 20%, 15%, 10%, 5%, or within 1% of the value or target. In further embodiments of the present invention, the term “substantially” is defined as approaching a specific numeric value or target to within 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1% of the value or target.
As used herein, the term “about” is used to indicate that exact values are not necessarily attainable. Therefore, the term “about” is used to indicate this uncertainty limit. In some embodiments of the present invention, the term “about” is used to indicate an uncertainty limit of less than or equal to ±20%, ±15%, ±10%, ±5%, or ±1% of a specific numeric value or target. In some embodiments of the present invention, the term “about” is used to indicate an uncertainty limit of less than or equal to ±1%, ±0.9%, ±0.8%, ±0.7%, ±0.6%, ±0.5%, ±0.4%, ±0.3%, ±0.2%, or ±0.1% of a specific numeric value or target.
Among other things, the present disclosure describes unique materials derived from recovered plastics and/or bioderived sources. For example, recovered products made of various polyesters may be deconstructed to smaller molecules (e.g., by glycolysis) followed by treating and/or reacting steps to produce useful intermediates capable of being reacted to manufacture useful polymers and/or resins. Examples of recovered plastics suitable for the methods described herein include polyethylene terephthalate (PET), glycol modified polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, and/or polyethylene 2,5-furandicarboxylate. Further, in some embodiments of the present disclosure, commodity polyesters may be converted to readily printable photopolymers. As shown herein, the final materials resulting from printable photopolymers possess comparable thermomechanical properties of comparable materials derived from petroleum on the market. As shown herein, by combining with biomass-derived monomers, some formulations may be optimized to provide an array of properties tailored to meet the requirements of the plastic's final use/application. Among other things, this work validates the concept of upcycling plastic waste through additive manufacturing to produce novel resins capable of competing with incumbent resins in a variety of final applications and products.
Referring again to
In some embodiments of the present disclosure, as described above, recovered PET may be deconstructed to yield a variety of hydroxyl group terminated deconstruction products, including BHET, which is shown below as Structure 1.
In some embodiments of the present disclosure, BHET may be derived by deconstructing a biomass-containing feedstock. However, BHET is just one example of a hydroxyl group terminated molecule that may be utilized to produce useful chemicals, polymers, and/or resins as described herein, by performing additional downstream processing as shown in
For the second structure (i.e., deconstruction product) shown in Scheme 1, u may be between 1 and 16. Also in Scheme 1, R2 is a bridging group with some suitable examples shown in Scheme 2 below.
In Scheme 2, the symbol represents a covalent bond to a neighboring atom (not shown). As described herein, a hydroxyl group terminated starting material may be reacted to replace at least a portion of the hydroxyl groups with a vinyl group-containing end-group. For example, deconstruction product BHET may be reacted with a functionalized reactant, in this case methacrylic anhydride (MAAH), to produce at least one functionalized intermediate, 1-(2-hydroxyethyl) 4-[2-[(2-methyl-1-oxo-2-propen-1-yl)oxy]ethyl] ester (shortened to “Mono-MB”), and/or 1,4-bis[2-[(2-methyl-1-oxo-2-propen-1-yl)oxy]ethyl] ester (shortened to “Di-MB”), shown below as Structures 2 and 3, respectively.
Thus, as described herein, a variety of molecules, derived from the deconstruction of plastics and/or bioderived may be utilized as starting materials to produce a variety of unique materials, e.g., polymers and resins, that provide replacements for existing materials. Functionalized intermediates Structures 2 and 3 above may be generalized as Structures 4 and 5 below, which, among other things describe the various combinations resulting from the deconstruction products summarized above in Schemes 1 and 2.
From Scheme 2 above, R1 may include the functionalized intermediates summarized in Scheme 3, where examples of R2 are shown in Scheme 2. Other possible reactive end-groups, R, positioned on functionalized intermediates include vinyl-containing reactive end-groups including methacrylate as summarized in Scheme 4 below. Such end-groups may result from reacting a variety of functionalized reactants, including methacrylic anhydride, methacrylic chloride, and/or methacrylic acid.
Referring to Scheme 3, in some embodiments of the present disclosure, u and n may each be between 1 and 10, inclusively. Generalized Structures 4 and Structure 5 may then be reacted (i.e., Step #3) to form various products, e.g., resins and polymers, as shown in generalized Reaction 1 illustrated in
As stated above, in some embodiments of the present disclosure, referring again to
Methacrylate reactions (Step #2 functionalizing) were carried out with various molar ratios of BHET and methacrylic anhydride, with the addition of 0.2 wt % of butylated hydroxytoluene (BHT) as a free-radical inhibitor and without the addition of a catalyst. The reactions were carried out for about 3 hours at a reaction temperature of about 140° C. Colorless liquid products were obtained, and subsequent purification was conducted by removing methacrylic acid (byproduct) under reduced pressure, for example between about 10 Torr and about 200 Torr and at a temperature between about 90° C. and about 120° C. Quantitative yields of the resultant functionalized intermediates are summarized in Table 1 below.
The degree of methacrylation was determined by 1H NMR. As the ratio of BHET to methacrylic anhydride decreased, the degree of methacrylation also decreased. Notably, while all five samples of functionalized intermediates were initially liquid at ambient conditions, crystallization was noticed from Samples 1, 2, 4 and 5, and only Sample 3 stayed as room-temperature-stable liquid. The viscosity of Sample 3 was determined on a TA ARES rheometer equipped with parallel plates with 100 um gap. Importantly, the viscosity of 1000 cP is suitable for common stereolithographic (SLA) and digital light processing (DLP) 3D printers. Furthermore, the glass transition temperatures (Tg) were measured by casting the resins resulting from the reacting of these functionalized intermediates in PTFE molds and subsequently cured under 405 nm UV light for 60 min at 5 mW/cm2. Dynamic mechanical analysis (DMA) was performed and the Tg was determined by the highest peak on tan δ curves. Referring to Table 1, Samples 1 and 5 were heated and melted to be fabricated into test specimens.
Sample 3 of Table 1 provided the optimum viscosity and a desirable Tg of 165° C. for the resultant resin, and, therefore, this functionalized intermediate was reacted in the 3D printer to produce the resultant resin. 1 wt % of a long wavelength UV photoinitiator, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), was added to the functionalized intermediate to provide suitable photoreactivity and light absorbance. Blue pigment was also added to the functionalized intermediate for aesthetic purposes. The printing process was carried out on an open-source desktop 3D printer (Zortrax) in 100 um layer height. Exemplary 3D printed resin products are illustrated in
Bisphenol A (BPA) derived resin has been widely used in today's SLA 3D materials. An ethoxylated BPA (EO/phenol=4) dimethacrylate from Miwon Specialty Chemical Co., Ltd. was chosen as a comparison to the BHET-derived resins described above. ASTM type V tensile bars (i.e., dogbones) were successfully printed under the same fabrication and post-printing processing conditions and were tested on an Instron tensile tester. Notably, the methacrylated BHET exhibited higher tensile strength and Young's modulus than those of the BPA resin, while the elongations of break were similar. Though preliminary, it is shown that the material properties of the BHET derived resin can match and possibly outperform the BPA resin.
Although the examples provided herein focus on methacrylate-functionalized intermediates for producing resins, other examples functionalized intermediates include vinyl groups, epoxy groups, and sulfur functional groups. Specific examples of functionalized intermediates include diallyl terephthalate, bis(allyloxyethyl)terephthalate, bis(mercaptoethyl)terephthalate, bis(mercaptopriopionicethyl)terephthalate, bis-glycidyl terephthalate, and bis(glycidylethyl)terephthalate, which are shown in Scheme 6 below, respectively. These molecules may be produced by reacting BHET with allyl alcohol, 2-allyl oxyl ethanol, mercaptoethanol, mercaptopropionic acid, epichlorohydrin, and excess amount of epichlorohydrin, respectively.
In some embodiments of the present disclosure, bioderived carboxylic acids, either as deconstruction products and/or derived by other means, may be reacted to form functionalized intermediates. A generalized reaction is shown in Reaction 3 below, reacting a dicarboxylic acid with glycidyl methacrylate.
Reaction 3 was performed using two exemplary bioderived dicarboxylic acids, adipic acid and itaconic acid. However, other dicarboxylic acids may also be used with examples including muconic acid, oxalic acid, malonic acid, maleic acid, succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, and/or sebacic acid. In some embodiments, referring to Reaction 3, a bioderived dicarboxylic acid may include the carboxylic acid functional groups separated by R, where R may be a carbon chain having between 1 and 20 carbon atoms. The carbon chain may be branched or linear and saturated or unsaturated. In some embodiments of the present disclosure, R may include other elements such as hydrogen, nitrogen, oxygen, sulfur, and/or phosphorus.
Adipic acid and itaconic acid were reacted with glycidyl methacrylate at a reaction temperature of about 140° C. for about three hours (using triphenylphosphine at 0.5 wt % as a catalyst). The structures resulting from Reaction 3 for adipic acid and itaconic acid are shown below in Scheme 7, respectively. When reacted (i.e., Step 3), resins were obtained having a Tg/° C. (DMA) of about 140° C. and greater than 250° C., respectively (“>250 indicates that the material maintained stiffness and did not become soft at temperatures of about 250° C. and below). Also, approximate viscosities of the final functionalized intermediates resulting from reacting adipic acid and itaconic acid where about 8,000 cps and about 20,000 cps, respectively.
Other methacrylate-functionalized intermediates may be obtained from a variety of bioderived acids. Examples of such bioderived acids include β-keto adipic acid, succinic acid, muconic acid, fumaric acid, saccharic acid, and furan dicarboxylic acid. These structures are summarized in Scheme 8 illustrated in
Scheme 9 summarizes some embodiments of R, as derived from β-keto adipic acid, succinic acid, muconic acid, fumaric acid, saccharic acid, and furan dicarboxylic acid, respectively.
Whether or not a reactant or product described herein is “bioderived” may be determined by analytical methods. Using radiocarbon and isotope ratio mass spectrometry analysis, the bio-based content of materials can be determined. ASTM International, formally known as the American Society for Testing and Materials, has established a standard method for assessing the biobased content of carbon-containing materials. The ASTM method is designated ASTM-D6866. The application of ASTM-D6866 to derive a “biobased content” is built on the same concepts as radiocarbon dating, but without use of the age equations. The analysis is performed by deriving a ratio of the amount of radiocarbon (14C) in an unknown sample to that of a modern reference standard. The ratio is reported as a percentage with the units “pMC” (percent modern carbon). If the material being analyzed is a mixture of present-day radiocarbon and fossil carbon (containing no radiocarbon), then the pMC value obtained correlates directly to the amount of biomass material present in the sample. Thus, ASTM-D866 may be used to validate that the compositions described herein are and/or are not derived from renewable sources.
Example 1. A composition comprising:
wherein: R comprises a reactive end group, R1 comprises a first bridging group, 1≤x≤100, and 1≤y≤100.
Example 2. The composition of Example 1, wherein: R comprises at least one of
and the symbol represents a covalent bond.
Example 3. The composition of either Examples 1 or 2, wherein: R1 comprises at least one of
R2 comprises a second bridging group, and 1≤u≤100.
Example 4. The composition of any one of Examples 1-3, wherein: R2 comprises at least one of
Example 5. The composition of any one of Examples 1-4, wherein: R1 is
Example 6. The composition of any one of Examples 1-5, further comprising:
wherein: 1≤m≤100, and 1≤n≤100.
Example 7. The composition of any one of Examples 1-6, comprising at least one of,
Example 8. The composition of any one of Examples 1-7, comprising a tensile strength between about 20 MPa and about 100 MPa.
Example 9. The composition of any one of Examples 1-8, comprising a modulus between about 0.5 GPa and about 3.0 GPa.
Example 10. The composition of any one of Examples 1-9, comprising an elongation at break between about 0.1% and about 100%.
Example 11. The composition of any one of Examples 1-10, comprising a glass transition temperature between about 0° C. and about 250° C.
Example 12. A method comprising: reacting a first functionalized intermediate with a second functionalized intermediate to form a product, wherein: the first functionalized intermediate comprises
the second functionalized intermediate comprises
the product comprises,
R comprises a reactive end group, R1 comprises a first bridging group, 1≤x≤100, and 1≤y≤100.
Example 13. The method of Example 12, wherein: the product further comprises
1≤m≤100, and 1≤n≤100.
Example 14. The method of either Examples 12 or 13, wherein: R1 comprises at least one of
R2 comprises a second bridging group, the symbol represents a covalent bond, and 1≤u≤100.
Example 15. The method of any one of Examples 12-14, wherein: R2 comprises at least one of
Example 16. The method of any one of Examples 12-15, wherein: R comprises at least one of
Example 17. The method of any one of Examples 12-16 wherein: R comprises
and the product comprises
Example 18. The method of any one of Examples 12-17, wherein: R1 comprises
and the product comprises
Example 19. The method of any one of Examples 12-18, further comprising: prior to the reacting, in a first mixture comprising a deconstruction product and a functionalized reactant, functionalizing the deconstruction product, wherein: the deconstruction product comprises
the functionalized intermediate comprises at least one of
and the functionalizing produces the first functionalized intermediate comprising
and the second functionalized intermediate comprising
Example 20. The method of any one of Examples 12-19, wherein: the first functionalized intermediate and the second functionalized intermediate are reacted at a molar ratio of the first functionalized intermediate to the second functionalized intermediate between about 1:2 and about 1:1 or between about 1:0.5 to about 1:1.
Example 21. The method of any one of Examples 12-20, wherein the first functionalized intermediate and the second functionalized intermediate form a second mixture having a viscosity between about 800 cP and 1200 cP at 25° C.
Example 22. The method of any one of Examples 12-21, wherein the reacting is performed at a temperature between 20° C. and 150° C. or between 20° C. and 50° C.
Example 23. The method of any one of Examples 12-22, wherein the reacting is photoinitiated at a wavelength between 254 nm and 500 nm.
Example 24. The method of any one of Examples 12-23, wherein the reacting is photoinitiated using at least one of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate (TPO-L), or phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (BAPO).
Example 25. The method of any one of Examples 12-24, wherein the product has a tensile strength between about 20 MPa and about 100 MPa.
Example 26. The method of any one of Examples 12-25, wherein the product has a modulus between about 0.5 GPa and about 3.0 GPa.
Example 27. The method of any one of Examples 12-26, wherein the product has an elongation at break between about 0.1% and about 100%.
Example 28. The method of any one of Examples 12-27, wherein the product has a glass transition temperature between about 0° C. and about 250° C.
Example 29. The method of any one of Examples 12-28, wherein the product comprises at least one of a polymer or a resin.
Example 30. The method of any one of Examples 12-29, further comprising: prior to the functionalizing, deconstructing a plastic, wherein: the deconstructing results in the forming of the deconstruction product.
Example 31. The method of any one of Examples 12-30, wherein the plastic comprises at least one of polyethylene terephthalate, glycol modified polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, or polyethylene 2,5-furandicarboxylate.
Example 32. The method of any one of Examples 12-31, wherein the deconstructing is performed by glycolysis.
The foregoing discussion and examples have been presented for purposes of illustration and description. The foregoing is not intended to limit the aspects, embodiments, or configurations to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the aspects, embodiments, or configurations are grouped together in one or more embodiments, configurations, or aspects for the purpose of streamlining the disclosure. The features of the aspects, embodiments, or configurations, may be combined in alternate aspects, embodiments, or configurations other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the aspects, embodiments, or configurations require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment, configuration, or aspect. While certain aspects of conventional technology have been discussed to facilitate disclosure of some embodiments of the present invention, the Applicants in no way disclaim these technical aspects, and it is contemplated that the claimed invention may encompass one or more of the conventional technical aspects discussed herein. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate aspect, embodiment, or configuration.
This application claims priority from U.S. Provisional Patent Application No. 63/050,912 filed on Jul. 13, 2020, the contents of which are incorporated herein by reference in its entirety.
This invention was made with government support under Contract No. DE-AC36-08GO28308 awarded by the Department of Energy. The government has certain rights in the invention.
Number | Date | Country | |
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63050912 | Jul 2020 | US |