| 摘要 |
PURPOSE:To obtain a terephthalic acid ester containing a few insoluble fine particles, by adding a polymerization catalyst before the first reactor and a heat stabilizer after the second one, using a plurality of reactors in series. CONSTITUTION:Terephthalic acid is esterified with ethylene glycol in a plurality of reactors in series. A polymerization catalyst, e.g. a Sb compound or together with a Co compound, is added to the reaction system before the first reactor; a heat stabilizer, e.g. a triphosphate, to the system after the second one. Esterification is carried out in the first reactor up to a rate of reaction of 60-95%, and then up to 92-98% in the reactors after the second one. EFFECT:Improved color and good spinning and drawing conditions due to the nearly completely suppressed formation of insoluble fine particles. |
