High-rigidity, high-melt-viscoelasticity polypropylene and process for producing the same.

摘要

A superior high-rigidity and high-melt-viscoelasticity polypropylene for sheets to be post-processed and for blow moulding is produced by subjecting propylene to a multi-stage polymerization into polymer portions of two sections in the presence of a specified Ziegler Natta catalyst, the relationship between the intrinsic viscosities of the polymer portions of the respective sections being regulated within a specific range and also the amount ratio of the polymer portions of the respective sections being regulated.