Abstract: The crystallization and melt behavior of polypropylene/montmorillonite nanocomposites (PMN) were investigated with DSC and XRD.The results showed that PMN presented higher melt point but lower relative crystallinity compared with that of pure PP.Moreover, more β crystal was found in PMN due to the existence of MMT as nucleation agent.At the same time, the appearance of β crystal restrained the growth of α crystal,decreasing its dimension.The effects of different contents, temperatures and shear speeds upon the shear viscosity of PMN were studied.The results showed that the system exhibited shear-thinning non-Newtonian behavior.As the content of MMT increased, the viscosity of the system decreased apparently.The processibility of PMN became better than pure PP.

Key words: 聚丙烯, 蒙脱土, 纳米复合材料, 力学性能, 结晶行为, 流变

摘要： 采用DSC及XRD研究了聚丙烯/蒙脱土纳米复合材料(PMN)的结晶熔融行为.DSC的结果表明，复合材料熔点升高，但相对结晶度下降.XRD结果表明，蒙脱土作为成核剂促进了聚丙烯β晶型的生成;同时β晶型的增长抑制了α晶体的长大，减小了α晶粒尺寸，提高了复合材料的力学性能.系统研究了复合材料的流变性能，探讨了蒙脱土含量、温度、剪切速率等因素对复合材料黏度特性的影响，结果表明，复合体系总体上呈现剪切变稀的特性，体系表观剪切黏度随蒙脱土含量的升高逐渐下降，材料加工性能优于聚丙烯基体.

关键词: 聚丙烯, 蒙脱土, 纳米复合材料, 力学性能, 结晶行为, 流变