研究了熔融共混法制备的不同共混比的等规聚丙烯(iPP)/顺丁橡胶(PcBR)合金的结晶特性及抗冲击性能。结果显示,随着ψ(PcBR)从0增至40%,iPP球晶的完整程度逐渐下降,球晶间的边界模糊化,球晶不断细化;PcBR的加入诱导了iPP的β晶型生成,其含量的增加导致合金中的微晶尺寸减小,晶面间距值基本不变,而长周期则明显增加;同时,合金的结晶峰所对应的温度有所升高,结晶速率明显增大,而相对结晶度减小,PcBR对iPP的结晶起到异相成核剂的作用;PcBR对iPP有显著的增韧效果。
This paper studied crystallization characteristics and impact property of isotactic polypropylene(iPP)/ poly(cis-butadiene) rubber(PcBR) alloys with different blend ratios. As volume content of PcBR went up from 0 to 40%, the crystal perfection of the iPP spherulite was deteriorated, the boundaries between the spherulites became vague and the size of the spherulites reduced. The introduction of PcBR induced the formation of iPP crystallites. The increase in content of PcBR led to a decrease in dimension of the crystallites in the alloy and a significant rise in long period of the crystallites, while the interplanar distance was kept basically unchanged. Simultaneously, the temperature corresponding the crystallization peak of the alloy rose somewhat and the crystallization rate increased obviously, but the relative crystallinity lowered. PcBR could not only act as a heterogeneous nucleating agent in the crystallization of iPP, but also play an important role of toughener to iPP.