两种改性剂增韧聚氯乙烯的结构、性能及增韧机理

The Structure, Properties and Toughening Mechanism of PVC Toughened and Modified by Two Modifiers

比较了两种改性剂对聚氯乙烯增韧改性共混体系微观结构和性能的影响。结果表明,随ABS和CPE用量增加,聚氯乙烯的冲击强度随之增加,但提高的幅度不同,CPE增韧效果优于ABS。CPE在共混体系中形成网络结构,受力时,CPE易与基体共同发生剪切屈服,产生“剪切带”;ABS以颗粒或聚集体分散在PVC连续相中,受力时ABS作为应力集中体引发“银纹”。

The influences of two modifiers, ABS and CPE, on the microstructure and properties of PVC/ABS and PVC/CPE were studied and compared. The experimental results showed that the impact strength of blending system increased with increasing the dosages of ABS and CPE. It was also found that ABS dispersed in the form of particles or aggregates in PVC matrix while CPE tended to disperse as a net-structure . In the tensile course, ABS initiated crazes as stress concentrators to toughen the PVC matrix, however, CPE with the PVC matrix together, gave a yield-deform by shear stress to form 'shear belt'.