Polypropylene interior parts for autocars

摘要

Polypropylene interior parts for autocars having overcome the drawback of their permanent bulge or secondary deformation due to high temperature exposure is provided, which parts are obtained by molding a material comprising a propylene-ethylene block copolymer prepared by polymerizing propylene at a first stage so that the resulting propylene homopolymer can have a relation between its isotactic pentad ratio (P) and MFR of 1.00>/=P>/=0.015 log MFR+0.955 and can occupy 70 to 95% by weight of the total polymerization quantity, followed by polymerizing ethylene or ethylene and propylene in 30 to 5% by weight of the total polymerization quantity at at least one stage, so as to give an ethylene content occupying 3 to 12% by weight of the total polymerization quantity.