Method for preparing bis(glycol)terephthalate oligomer and polyester resin
AssigneeSK Chemicals Co., Ltd.
InventorsDa-Young HWANG, Yoo Jin LEE
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Abstract
According to the present invention, bis(glycol)terephthalate can be prepared by a transesterification reaction of glycol and bis(2-hydroxyethyl)terephthalate and then introduced to a polymerization reaction to increase the content of recycled raw materials in a polyester resin. In addition, purity is improved through the removal of impurities by extracting glycol byproducts during the transesterification reaction, and thus the quality of the final resin can be improved while reducing the amount of byproducts from the polymerization reaction.
Claims20
A process for preparing a polyester resin, which comprises:
- subjecting bis(2-hydroxyethyl) terephthalate to a transesterification reaction with a glycol having 3 or more carbon atoms;
- collecting and removing ethylene glycol as a by-product formed during the transesterification reaction;
- obtaining a bis(glycol) terephthalate oligomer as a product of the transesterification reaction;
- and
- conducting a polymerization using the bis(glycol) terephthalate oligomer.
A process for preparing a bis(glycol) terephthalate oligomer, which comprises:
- subjecting bis(2-hydroxyethyl) terephthalate to a transesterification reaction with a glycol having 3 or more carbon atoms;
- and
- collecting and removing ethylene glycol as a by-product formed during the transesterification reaction.
Dependencies are inferred from the claim text.