PREPARATION METHOD OF ENVIRONMENT-FRIENDLY POLYESTER COPOLYMER WITH GOOD TRANSPARENCY

摘要

PURPOSE: A method for preparing an environment-friendly polyester copolymer is provided, to improve the transparency and heat stability of the polyester copolymer and to allow the method to be applied the industrial production. CONSTITUTION: The method comprises the steps of esterifying dimethyl terephthalate, ethylene glycol and/or 1,4-cyclohexane dimethanol in the presence of a complex catalyst which consists of an antimony compound and a titanium/phosphorus-based compound by the mass ratio of 1 : 0.5-5.0 and is dissolved in ethylene glycol, to obtain esterified compound in low polymerization; and polycondensing the obtained compound. Preferably the esterification temperature is 200-260 deg.C; the polycondensation temperature is 260-300 deg.C; and dissolution temperature of the complex oxide is 20-200 deg.C.