1. Introduction
It has become an active area of the polymeric industry to make an optimum property polypropylene PP by many methods, including mixing, filling and nucleation.In industrial practice, the final properties of PP are often further adjusted through the addition of
nucleating agents. This kind of heterogeneous nucleation takes advantage of higher crystallization velocities,thus arriving at a higher crystallinity and a finer morphology on the spherulithic level. Therefore, the variation of the impact properties of the materials is due to the comprehensive results of the two kinds of morphology parameters. In this paper, an effort was made, not only to analyze the comprehensive effect of spherulite size and crystallinity on impact properties,but also to try to make clear their separate effects.