The crystallinity of polypro pylene

grain size and distribution

and the morphology of spherulite affect its mechanical properties greatly

especially the impact strength. Polypropylene alloy has better impact strength for its smaller spherulite and more defect in spherulite. And polypropylene alloy has better performance if the spherulite has moderate size and uniform distribution. The crystallinity of copolymer also affect the mechanical properties of polypropylene alloy

and increasing the crystallinity of copolymer mayincreasing its impact strength.