Patent ID: 10465041

Abstract:
A method for preparing the modified polyester. The modified polyester segments include terephthalic acid segment, ethylene glycol diol segment and branched diol segment, in which the branched diol segment refers to a diol segment in which a branch is located on a non-terminal carbon in the glycol segment and the branch is a linear carbon chain having 5 to 10 carbon atoms. The method includes preparing terephthalic acid glycol ester through the esterification of terephthalic acid and branched diol using the concentrated sulfuric acid as the catalyst. Then get ethylene terephthalate through the esterification of terephthalic acid and ethylene glycol. After stirring and mixing the two, the modified polyester can be obtained through polycondensation reaction of a low vacuum stage and a high vacuum stage using the catalyst and stabilizer.