助剂对铝基催化剂合成PET性能的影响

Effect of Auxiliaries on the Properties of PET Synthesized by Aluminum Based Catalysts

根据铝基催化剂合成聚对苯二甲酸乙二醇酯(PET)具有活性高、价格低等优点,但b值较高等不足,研究了磷酸三苯酯、三(2,4-二叔丁苯基)亚磷酸酯(抗氧剂168)、四[3-(3,5-二叔丁基-4-羟苯基)丙酸]季戊四醇(抗氧剂1010)、硫代二丙酸双十二烷酯、4,4'-亚甲基双(2,6-二叔丁基本酚)等助剂对铝基催化剂合成PET的特性黏数、端羧基含量、二甘醇(DEG)含量、b值、热稳定性、分子量及分布的影响。结果表明,磷酸三苯酯(TPP)、168和1010均能降低PET中的端羧基和DEG含量,但TPP和168单独使用时会导致PET特性黏数下降;复合助剂中,当w(168)/w(1010)=1、用量为400×10^(-6)时合成的PET性能最好,端羧基和DEG含量分别为25.6mol/t和2.95%、多分散系数(PDI)为2.31、b值为3.8,PET在空气中的初始分解温度(T_(d(5%)))升高至373℃。

The poly（ethylene terephthalate）（PET） synthetized by aluminum based catalysts had the advantages of high activity and low price but high b value.Thus,the paper studied the effects of triphenyl phosphate（TPP）,antioxidantstris（2,4-ditert-butylphenyl） phosphate（168）,pentaerythritoltetrakis（3-（3,5-di-tert-butyl-4-hydroxyphenyl） propionate）（1010）,dilauryl thiodipropionate,4,4＇-methylenebis（2,6-di-tert-butyl-phenol） and other auxiliaries on the intrinsic viscosity,the content of carboxyl end group and diethylene glycol（DEG）,b value,thermal stability,relative molecular mass and its distribution of PET synthetized by aluminum based catalysts.The results show that TPP,168 and 1010 can reduce the content of carboxyl end group and DEG in PET,but the intrinsic viscosity of PET could be decreased when TPP and 168 are used alone;among the compound auxiliaries,when w（168）/w（1010） =1 and the dosage is 400×10-（-6）,the properties of PET is the best：the content of carboxyl end group and DEG is 25.6 mol/t and 2.95% respectively,polydispersity index is 2.31,b value is 3.8,and the initial decomposition temperature（T（d（5%））） in the air is raised to 373 ℃.