α-成核剂对PP/SEPS共混体系脆-韧转变的影响

Effect of α-Nucleating Agent on Brittle-ductile Transition of PP/SEPS Blends

采用熔融共混法制备了具有不同α-成核剂(α-NA)含量的聚丙烯(PP)和氢化苯乙烯-异戊二烯-苯乙烯嵌段共聚物(SEPS)共混体系,通过扫描电子显微镜观察了不同共混体系分散相的粒子尺寸及分布,根据逾渗模型计算了不同共混体系的粒子间距,定量描述了α-NA含量对共混体系临界粒子间距的影响。结果表明,α-NA的含量越高,共混体系的临界粒子间距越大,越有利于脆-韧转变的发生。

PP/SEPS blends containing a-nucleating agent （α-NA） were prepared by melt mixing process. And the particle size and distribution of dispersed phase were measured by scanning electron microscopy. The inter-particle distance in the blendS with different content of α-NA was calculated according to a percolation model, and the effect of content of α-NA on the critical inter- particle distance was described quantitatively. It was found that the higher the content of α-NA, the greater the inter-particle distance, and the easier the brittle-ductile transition.