中国昆仑工程公司开发出一种适于聚对苯二甲酸丙二醇酯制备的复合催化剂以及采用这种复合催化剂的聚对苯二甲酸丙二醇酯制备新方法。复合催化剂包括钛酸正四丁酯和亚磷酸酯,钛酸正四丁酯和亚磷酸酯的质量比优选为0.6~1.15。以对苯二甲酸和1,3-丙二醇为原料,以上述复舍催化剂为催化剂,经酯化 Kunlun Engineering Company of China has developed a composite catalyst suitable for the preparation of poly (trimethylene terephthalate) and a new method for the preparation of poly (trimethylene terephthalate) using this composite catalyst. The composite catalyst includes n-tetrabutyl titanate and phosphite, and the mass ratio of n-tetrabutyl titanate and phosphite is preferably 0.6 to 1.15. Terephthalic acid and 1,3-propanediol as raw materials, the above compound homes catalyst as a catalyst, the esterification