Polymer composition for bumpers and interiors and polyethylene-based resin precursor

摘要

Polyolefin compositions suitable for injection moulded items e.g. for impact bumpers and car interiors comprising from 30% to 90% by weight of an heterophasic propylene polymer composition (A); and from 10% to 70% by weight of a multimodal ethylene/C6-C12 alpha olefin copolymer (B); having density from 0.850 to 0.920 g/cm3, total comonomer content from 6% to 30% by weight, Mw/Mn from 4 to 20; intrinsic viscosity in decalin at 135° C. from 1.0 to 4.0 dL/g, and comprising an HDPE fraction (HDPE % wt) up to 30% wt; further comprising up to 50% by weight of a filler (C) and optionally, in amount up to 10% by weight with respect to the overall composition, an impact modifier masterbatch component (D) consisting of a ultra-soft heterophasic copolymer component.

主权项

1. A polyolefin composition comprising:
A) from 30% to 90% by weight of a propylene polymer composition comprising:
a1) from 20% to 90% by weight of a propylene homopolymer, or a copolymer of propylene or blends thereof containing 8% by weight or less of copolymerized ethylene or C4-C10 α-olefin(s) or blends thereof, said homopolymer or copolymer or blends having an isotactic index greater than 80%,a2) from 10% to 80% by weight of a copolymer of ethylene containing from 40% to 70% of copolymerized propylene or C4-C10 α-olefin(s) or of combinations thereof;said composition A having intrinsic viscosity of the xylene soluble fraction at room temperature of from 1.5 to 8 dl/g; B) from 10% to 70% by weight of a multimodal ethylene copolymer wherein the comonomer is selected from alpha olefins of formula CH2═CHT wherein T is a C3-C10 alkyl group; having the following properties:
i) density comprised in the range from 0.850 to 0.920 g/cm3 as measured according to ISO1183-1::2004;ii) total comonomer content ranging from 6% to 30% by weight;iii) Mw/Mn comprised from 4 to 20;iv) intrinsic viscosity, as determined in decalin at 135° C. according to EN ISO 1628-312003, comprised between 1.0 and 4.0 dL/g, and wherein the multimodal ethylene copolymer comprises an HDPE fraction (HDPE % wt) determined via TREF analysis of up to 30% wt; and C) up to 50% by weight of a filler.