摘要
聚氯乙烯(PVC)容易发生脱氯化氢的热降解。研究者普遍认为,这是由于PVC分子链中存在结构缺陷而引起的。对究竟何种结构缺陷是引起PVC热不稳定的主要根源这一重要问题,虽然已有许多研究者进行过研究,但由于他们得到的结果往往各不相同,因而迄今未能达到一个明确一致的结论。如Minsker认为羰基烯丙基氯结构是引发脱HCl的主要原因。但Starnes却持相反意见。
Five PVC samples (U-PVC) were prepared in water suspended system at monomer unsa-turation vapor pressure. The molecular weigh's and dehydrochlorination rates (De-HCl) of these samples and five commercial PVC samples (S-PVC) were determined. Experimental data showed that the thermal stabilities and molecular weights of U-PVC samples decreased wifh decreasing the monomer unsaturation vapor pressure (Pm/Po) in the preparation process. It was found also that there was a good linear correlation between 1/Mm, De-HCl and Pm/P0 This result indicated the important .role of the terminal structural defect in the dehydrochlorination of PVC. The mechanism of formation of terminal structural uefects was discussed.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
1992年第2期246-250,共5页
Acta Polymerica Sinica
基金
国家自然科学基金
关键词
聚氯乙烯
结构缺陷
热不稳定性
Poly (vinyl chloride), Structural defect, Dehydrochlorination rate, Thermal stability
