【摘要】 用悬浮聚合方法制得了氯乙烯 N 苯基马来酰亚胺 ( 丙烯腈 )共聚物 ,研究了该共聚物的维卡软化点、玻璃化温度、动态力学行为以及形态结构 .发现当耐热组分达到一定含量时 ,耐热性能的增加幅度发生变化、出现两个动态力学内耗峰、形态上出现双连续相结构 .基于这些实验现象 ,提出了“刚性有效网架”可以使耐热性能大幅度提高的观点 ,并探讨了耐热机理 ,给出了物理模型 .讨论了相容性对“刚性有效网架”形成的影响更多还原

【Abstract】 The heat resistant properties of polyvinyl chloride (PVC) are very poor,so that PVC resin can not be used in many cases.In order to enhance the heat resistant properties of PVC, N -phenyl maleimide (PMI) and/or acrylonitrile (AN) monomer units were introduced into the PVC chain to prepare heat resistant VC-PMI copolymer and VC-PMI-AN terpolymer by suspension polymerization.The Vicat softening point (VSP),glass transition temperature ( T g),dynamical mechanical behavior and morphological structure of heat resistant VC-PMI copolymer and VC-PMI-AN terpolymer were studied in detail.The results showed that the VSP and T g of the heat resistant PVC increased with the content of PMI or AN.When the content of the heat resistant monomer units was high than a critical value,the increasing rate of the heat resistant properties was changed,two tan δ peaks appeared,and a dual phase continuity structure,named as “stiff chain frame work",was formed.On the basis of these experimental phenomena,a new concept that the “stiff chain frame network" can increase the heat resistant properties of the heat resistant PVC was presented.A heat resistant mechanism was discussed and its physical model was proposed also.The results of dynamic mechanical analysis revealed that the polymers had only one tan δ peak in most cases,however,two tan δ peaks appeared with increasing of the content of AN.The miscibility of the heat resistant agent (VC-PMI copolymer or VC-PMI-AN terpolymer) and PVC will influence the formation of the “stiff chain frame network".更多还原