公开(公告)号：CA1038996A

公开(公告)日：1978-09-19

申请号：CA237205

申请日：1975-10-07

Applicant: BASF AG

Inventor： REBHAN JOERG ,  MATTHIES HANS G

IPC: C08G63/00 ,  C07C69/82 ,  C08G63/78 ,  C08G63/18 ,  C08G63/60

Abstract: An improved process for the continuous manufacture of linear high molecular weight polyesters by direct esterification of terephthalic acid with excess glycols in a medium comprising terephthalic acid glycol esters or their oligomers, under superatmospheric pressure at temperatures above 200.degree.C, followed by polycondensation in the presence Or catalysts at from 260 to 290.degree.C. The improvement is that the mixture fed to the esterification contains terephthalic acid and glycols in the molar ratio of 1:1.15 to 1:1.5 and that during the esterification from 20 to 30% by weight Or the excess of glycols over the molar ratio terephthalic acid:glycols = 1:1 are continuously distilled from the reaction mixture.