CN-121991330-A - Process for producing thermoplastic polyester elastomer

Abstract

The present invention provides a method for producing a thermoplastic polyester elastomer, comprising the steps of providing a polyester recycled product comprising polyethylene terephthalate, performing a first depolymerization step comprising mixing the polyester recycled product with polyethylene terephthalate oligomer to perform an extrusion depolymerization to obtain at least polyethylene terephthalate polymer, and performing a polymerization step comprising adding a long chain type polyalkyl glycol to perform a polymerization reaction to obtain at least a thermoplastic polyester elastomer.

Inventors

• YUAN JINGYAO
• CHEN ZHONGYU
• HUANG ZHANGJIAN
• ZHANG MENGCHEN

Assignees

• 南亚塑胶工业股份有限公司

Dates

Publication Date

20260508

Application Date

20250103

Priority Date

20241105

Claims (10)

1. 1. A method of making a thermoplastic polyester elastomer comprising: the provision of a polyester recycle is provided, which, the polyester recyclate comprises polyethylene terephthalate, Performing a first depolymerization step comprising mixing the polyester recycle with a polyethylene terephthalate oligomer to effect an extrusion depolymerization to obtain at least a polyethylene terephthalate polymer, and A polymerization step is performed which comprises adding a long chain polyalkyl glycol to perform a polymerization reaction to obtain at least a thermoplastic polyester elastomer.
2. 2. The method of making a thermoplastic polyester elastomer according to claim 1, wherein the polyethylene terephthalate oligomer comprises bishydroxyethyl terephthalate, polyethylene terephthalate dimer, polyethylene terephthalate trimer, mono (2-hydroxyethyl) terephthalic acid, or a combination thereof.
3. 3. The method of making a thermoplastic polyester elastomer of claim 1, wherein the long chain polyalkyl glycol comprises polyethylene glycol, polytetramethylene ether glycol, or a combination thereof.
4. 4. The method for producing a thermoplastic polyester elastomer according to claim 1, wherein the amount of the long-chain polyalkyl glycol added in the polymerization step is 20 to 60% by weight based on the total weight of the reactants of the polymerization reaction.
5. 5. The method for producing a thermoplastic polyester elastomer according to claim 1, further comprising: A second depolymerization step is performed, comprising mixing the polyethylene terephthalate polymer with a depolymerization liquid to perform chemical depolymerization to obtain at least a bishydroxyethyl terephthalate monomer.
6. 6. The method for producing a thermoplastic polyester elastomer according to claim 5, further comprising: performing a transesterification step comprising mixing the dihydroxyethyl terephthalate monomer with an aliphatic diol to perform a transesterification reaction to obtain a product, The product comprises dihydroxypropyl terephthalate, dihydroxybutyl terephthalate, or a combination thereof.
7. 7. The method for producing a thermoplastic polyester elastomer according to claim 6, wherein the aliphatic diol comprises a diol having 3 to 10 carbon atoms.
8. 8. The method for producing a thermoplastic polyester elastomer according to claim 6, wherein the polymerization step comprises mixing the product with the long-chain polyalkyl glycol to perform the polymerization reaction to obtain at least the thermoplastic polyester elastomer.
9. 9. The method for producing a thermoplastic polyester elastomer according to claim 1, wherein the step of polymerizing comprises mixing the polyethylene terephthalate polymer with the long-chain polyalkyl glycol to perform polymerization reaction to obtain at least the thermoplastic polyester elastomer.
10. 10. The method for producing a thermoplastic polyester elastomer according to any one of claims 1 to 9, wherein a catalyst is further added in the first depolymerization step, the second depolymerization step, and/or the polymerization step.

Description

Process for producing thermoplastic polyester elastomer Technical Field The present invention relates to a method for producing a thermoplastic polyester elastomer, and in particular to a method for producing a thermoplastic polyester elastomer comprising extrusion depolymerization. Background Polyester products are widely used in life and thus produce a lot of polyester waste. The current methods for recycling waste with esters often use large amounts of glycols for extrusion alcoholysis. However, the diols are subject to high temperature vaporization, resulting in dangerous recovery processes and poorly controlled reactions. Therefore, how to effectively recycle and/or treat polyester waste is the subject of current research. Disclosure of Invention The invention provides a method for producing a thermoplastic polyester elastomer, which can effectively recycle polyester recycled materials and reduce recycling cost. A method for producing a thermoplastic polyester elastomer of the present invention comprises the steps of providing a polyester recycled product comprising polyethylene terephthalate (polyethylene terephthalate, PET), performing a first depolymerization step comprising mixing the polyester recycled product with a polyethylene terephthalate oligomer to perform extrusion depolymerization to obtain at least a polyethylene terephthalate polymer, and performing a polymerization step comprising adding a long-chain type polyalkyl glycol to perform polymerization to obtain at least a thermoplastic polyester elastomer (thermoplastic polyester elastomer, TPEE). In one embodiment of the present invention, the polyethylene terephthalate oligomer includes bis (2-HydroxyEthyl Terephthalate), BHET, polyethylene terephthalate dimer (dimer), polyethylene terephthalate trimer (trimer), mono (2-hydroxyethyl) TEREPHTHALIC ACID, MHET, or a combination thereof. In one embodiment of the present invention, the long-chain polyalkyl glycol includes polyethylene glycol (polyethylene glycol, PEG), polytetramethylene ether glycol (polytetramethylene ether glycol, PTMEG), or a combination thereof. In an embodiment of the present invention, the amount of the long-chain polyalkyl glycol added in the polymerization step is 20 to 60% by weight based on the total weight of the reactants of the polymerization reaction. In one embodiment of the present invention, the above-mentioned manufacturing method further comprises performing a second depolymerization step comprising mixing polyethylene terephthalate polymer with the depolymerization liquid to perform chemical depolymerization to obtain at least the dihydroxyethyl terephthalate monomer. In an embodiment of the present invention, the above manufacturing method further comprises performing a transesterification step, which comprises mixing a dihydroxyethyl terephthalate monomer with an aliphatic diol to perform a transesterification reaction to obtain a product. The product comprises bis-hydroxypropyl terephthalate (bis-hydroxypropyl terephthalate, BHPT), bis-hydroxybutyl terephthalate (bis-hydroxybutyl terephthalate, BHBT), or a combination thereof. In an embodiment of the invention, the aliphatic diol includes a diol having 3 to 10 carbon atoms. In one embodiment of the present invention, the step of polymerizing comprises mixing the product with a long chain polyalkyl glycol to effect polymerization to obtain at least a thermoplastic polyester elastomer. In one embodiment of the present invention, the step of polymerizing comprises mixing the polyethylene terephthalate polymer with a long chain polyalkyl glycol to perform a polymerization reaction to obtain at least a thermoplastic polyester elastomer. In an embodiment of the invention, the first depolymerization step, the second depolymerization step and/or the polymerization step further includes adding a catalyst. Based on the above, the method for producing a thermoplastic polyester elastomer of the present invention comprises mixing a polyester recycled product with a polyethylene terephthalate oligomer, and then subjecting the mixture to a depolymerization step and a polymerization step, wherein the depolymerization step is extrusion depolymerization. Therefore, the waste polyester can be effectively recovered, and the recovery cost of the polyester can be reduced, so that the environmental burden is reduced, and the effects of environmental protection and recycling economy are achieved. In order to make the above features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below. Drawings FIG. 1 is a schematic flow chart of a method of manufacturing a thermoplastic polyester elastomer in accordance with an embodiment of the invention. Description of the reference numerals S100, S105, S110, S120, S130, S140 steps Detailed Description The following is a detailed description of embodiments of the present invention. The implementation details presente