摘要
由TGA测定了通过先酯化、再缩聚方法合成的PET-PTT共聚酯(以PET,PTT作对照)在一定升温速率下氮气及空气气氛中的热失重行为。采用Friedman和Chang方法研究了样品的降解动力学。研究表明,在氮气和空气气氛中PET-PTT共聚酯的热稳定性都介于PET和PTT之间,且随着PET链段单元含量的增加,共聚酯的热稳定性提高。气氛对聚合物降解行为的影响很大,在空气中PET-PTT共聚酯的起始分解温度下降了近50℃,且在空气气氛中存在两个降解阶段,空气中的氧在降解的第一阶段起了催化剂的作用。
Thermal gravitation analyses of a series of poly（ethylene-co-trimethylene terephthalate） （PET-PTT） copolyesters prepared by direct esterification and a sequential polycondensation were carried out under a certain heating rate in nitrogen and air, the results were aim compared with those of PET and PTT homopolymers. Friedman and Chang techniques were used to analyze dynamic thermogravimetric kinetics of all the samples. It shows that under both nitrogen and air atmosphere, the thermal stability of PET-PTT copolyesters is intervenient between PET and PTT, and increases with an increasing content of PET units. For all samples the onset degradation temperature decreases about 50 ℃ in air compared to that in nitrogen and shows two weight-loss stages. From the analysis of decomposition kinetic, it can be deduced that the oxygen in air acts as catalyzer in the first weight-loss stage, resulting in the decrease of onset degradation temperature as well as the lower degradation activation energy and rate.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2009年第1期63-66,共4页
Polymer Materials Science & Engineering
关键词
PET—PTT共聚酯
热稳定性
热氧稳定性
poly（ethylene-co-trhnethylene terephthalat）
thermal degradation
thermal-oxidative degradation
