改性聚丙烯的结晶行为和熔体强度研究

Study on Crystallization Behavior and Melt Strength of Modified Polypropylene

将实验室自制的长链支化聚丙烯与线性聚丙烯熔融共混,对线性聚丙烯进行了改性,研究了共混改性体系的熔体强度与结晶行为。结果表明,长链支化聚丙烯显著提高了线性聚丙烯的熔体强度。异相成核作用的存在使得共混体系的结晶温度较线性聚丙烯显著提高,结晶速度快,所形成的球晶数量多且尺寸小。

The linear polypropylene was modified by blending with the long chain branching polypropylene prepared in laboratory. The melt strength and crystallization behavior were studied. The results indicate that： long chain branched polypropylene significantly increases the melt strength of linear polypropylene. The existence of heterogeneous nucleation increases the crystallization temperature of the blends, and the crystallization rate is faster than that of linear polypropylene.