【摘要】 阐明了聚对苯二甲酸乙二酯缩聚过程中热降解与羧基含量的关系.发现,钛酸四丁酯或草酸亚锡作为缩聚催化剂时,在整个高真空阶段羧基含量并不是一直增加的.采用三种方法(TGA、[η]和COOH)求热氧化降解速度常数,并对其结果进行了讨论.探讨了单一或复合稳定剂和缩聚催化剂对热氧化降解的影响.更多还原

【Abstract】 The relation between thermal degradation and carboxyl content of polyethylene tereph-thalate is investigated in the polycondensation process. It is found that in the presence of butyl titanate or stannous oxalate as a polycondensation catalyst the carboxyl content is not always on the increase in all high vacuum stage. Three methods (TGA, [η] and COOH) for evaluating thermooxidative degradation rate constants are employed and the results are discussed. The effects of single or composite stabilizers and polycondensation catalysts on the thermooxidative degradation have also been studied.更多还原