초록

The present disclosure relates to the formation of terephthalate esters. The present invention also relates to the depolymerization of polyethylene terephthalate (PET) or poly(ethylene glycol-co-1,4-cyclohexanedimethanol terephthalate) and the recovery of terephthalate esters.

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1. A process for the transformation of a polyester selected from the group consisting of polyethylene terephthalate and poly(ethylene glycol-co-1,4-cyclohexanedimethanol terephthalate) into a terephthalate of Formula (I): wherein R1 and R2 are independently selected from the group consisting of hydr

1. A process for the transformation of a polyester selected from the group consisting of polyethylene terephthalate and poly(ethylene glycol-co-1,4-cyclohexanedimethanol terephthalate) into a terephthalate of Formula (I): wherein R1 and R2 are independently selected from the group consisting of hydrogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 hydroxyalkyl, optionally substituted C3-C8 cycloalkyl, optionally substituted (C1-C6 alkyl)(C3-C8 cycloalkyl), optionally substituted aryl, and optionally substituted (C1-C6 alkyl)(aryl); provided that one of R1 or R2 is not hydrogen;the process comprising admixing the polyester with a mixture comprising: (a) a solvent for swelling the polyester;(b) an alcoholic solvent; and(c) a sub-stoichiometric amount of an alkoxide;wherein the process is performed at a temperature between about 25° C. and about 80° C.;wherein the ratio of the polyester to the alkoxide is between about 20:1 and about 50:1 (w:w); and wherein the admixing is performed to achieve at least about 70% yield of the terephthalate of Formula (I). 2. The process of claim 1, wherein R1 or R2 is methyl. 3. The process of claim 1, wherein the alcoholic solvent is selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, t-butanol, ethylene glycol, glycerol, cyclohexane-1,4-diyldimethanol, phenol, benzyl alcohol, and any combinations thereof. 4. The process of claim 3, wherein the alcoholic solvent is methanol. 5. The process of claim 1, wherein the solvent for swelling the polyester is selected from the group consisting of a non polar solvent, a polar aprotic solvent, a polar protic solvent, and any combinations thereof. 6. The process of claim 1, wherein the solvent for swelling the polyester is selected from the group consisting of DMSO, DMF, acetone, a halogenated solvent, n-hexane, nitrobenzene, methanol, benzyl alcohol, benzaldehyde, and any combinations thereof. 7. The process of claim 1, wherein the solvent for swelling the polyester is a halogenated solvent. 8. The process of claim 1, wherein the ratio of the solvent for swelling the polyester to the alcoholic solvent is between about 0.1:1 and about 2:1 (w:w). 9. The process of claim 1, wherein the ratio of the solvent for swelling the polyester to the alcoholic solvent is between about 0.5:1 and about 1:1 (w:w). 10. The process of claim 1, wherein the alkoxide is selected from the group consisting of an alkali metal alkoxide, an alkaline earth metal alkoxide, a metal alkoxide, an ammonium alkoxide and any combinations thereof. 11. The process of claim 1, wherein the alkoxide is generated in-situ by addition of an alkali metal, an alkaline earth metal, or a metal to the alcoholic solvent. 12. The process of claim 1, wherein the ratio of the polyester to the alkoxide is between about 20:1 and about 25:1 (w:w). 13. The process of claim 1, wherein the admixing of the polyester with the solvent for swelling the polyester, the alkoxide, and the alcoholic solvent is performed to achieve at least about 80% yield of the terephthalate of Formula (I). 14. The process of claim 1, wherein the admixing of the polyester with the solvent for swelling the polyester, the alkoxide, and the alcoholic solvent is performed at atmospheric pressure. 15. A process for the transformation of polyethylene terephthalate into dimethyl terephthalate, comprising admixing the polyethylene terephthalate with a mixture comprising: (a) a solvent for swelling the polyethylene terephthalate;(b) methanol; and(c) a sub-stoichiometric amount of an alkoxide; wherein the process is performed at a temperature between about 25° C. and about 80° C.; wherein the ratio of the polyethylene terephthalate to the alkoxide is between about 20:1 and about 50:1 (w:w); and wherein the admixing is performed to achieve at least about 70% yield of dimethyl terephthalate. 16. The process of claim 15, wherein the solvent for swelling the polyethylene terephthalate is selected from the group consisting of a halogenated solvent, DMSO, benzyl alcohol, methanol, and any combinations thereof. 17. The process of claim 15, wherein the ratio of the polyethylene terephthalate to the alkoxide is between about 20:1 and about 25:1 (w:w). 18. The process of claim 15, wherein the alkoxide is selected from the group consisting of sodium methoxide, potassium ethoxide, aluminium tri-n-propoxide, and tetrabutylammonium methoxide. 19. The process of claim 15, wherein the ratio of the solvent for swelling the polyethylene terephthalate to the methanol is between about 0.5:1 and about 1:1 (w:w). 20. The process of claim 15, wherein the admixing of the polyethylene terephthalate with the solvent for swelling the polyethylene terephthalate, the alkoxide, and the methanol is performed to achieve at least an about 80% yield of dimethyl terephthalate.