| 摘要 |
Disclosed is a process for preparing linear, high molecular weight copolyesters from either (A) polyesters or copolyesters, the acid component of which consists of at least 70 mole percent terephthalic acid and the diol component of which consists of at least 70 mole percent ethylene glycol or (B) copolyesters, the acid component of which consists of at least 70 mole percent terephthalic acid and the diol component of which consists of at least 70 mole percent of a mixture of ethylene glycol and 1,4-cyclohexanedimethanol in a mole ratio of from 20:80 to 97:3, the process comprising heating the polymer in the presence of 1,4-cyclohexanedimethanol to glycolize the polymer, distilling out ethylene glycol from the glycolysis mixture, and polycondensing the glycolysis mixture to form a copolyester of which at least a portion of ethylene glycol units are replaced by 1,4-cyclohexanedimethanol units. The process provides a fast polymerization rate and the polymers so produced can be used in the manufacture of plastics, fibers, films and other shaped objects having good physical properties.
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