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

Patent metadata

Field	Value
Publication number	US-9650505-B2
Application number	US-201214357503-A
Country	US
Kind code	B2
Filing date	Oct 30, 2012
Priority date	Nov 11, 2011
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

Polyolefin compositions suitable for injection molded 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/butene-1 copolymer (B); having density from 0.850 to 0.935 g/cm 3 , 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 from 0 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 an ultra-soft heterophasic copolymer component.

First claim

What is claimed is:

1. A polyolefin composition comprising:
A) 30% to 90% by weight of a propylene polymer composition comprising:
a1) 20% to 90% by weight of a propylene homopolymer or of a copolymer of propylene or blends thereof, containing 3% by weight or less of copolymerized ethylene or C 4 -C 10 α-olefin(s) or blends thereof, said homopolymer or copolymer or blends having an isotactic index higher than 96%,
a2) 10% to 80% by weight of a copolymer of ethylene containing 40% to 70% by weight of copolymerized propylene or C 4 -C 10 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 according to ASTM D 2857;

B) 10% to 70% by weight of a multimodal ethylene copolymer with butene-1 as comonomer comprising:
i) a density in the range from 0.850-0.935 g/cm 3 as measured according to ISO1183-1::2004;
ii) a total butene-1 comonomer content ranging from 6-30% by weight;
iii) a Mw/Mn value from 4 to 20 as measured by gel phase chromatography;
iv) an intrinsic viscosity, as determined in decalin at 135° C. according to EN ISO 1628-312003, between 1 and 4 dl/g,

further comprising an HDPE fraction determined via TREF analysis of up to 30% by weight;
C) up to 50% by weight of a filler.

2. The polyolefin composition according to claim 1 , further comprising:
D) up to 10% by weight, with respect to the overall composition, of an impact modifier masterbatch consisting of an heterophasic copolymer component comprising:
a) 10-45% by weight of a homopolymer or a copolymer of propylene;
b) 10-30% by weight of a copolymer of propylene with ethylene, containing from 18-45% of ethylene;
c) 35-60% by weight of a copolymer of propylene with ethylene, containing from 55-85% by weight of ethylene;
said component (D) having a MFR L measured at 230° C./2.16 kg according to ISO 1133:2005 of from 0.01 to 10 g/10 min., a value of the Intrinsic viscosity of the fraction soluble in xylene at room temperature (XSIV) of from 1.5 to 3 dl/g and a value of the ratio XSIV/MFR L equal to or lower than 6.

3. An injection molded article comprising the polyolefin composition of claim 1 .

4. The injection molded article of claim 3 , wherein the article is selected from a bumper, a bumper cover, an exterior fascia, an air dam, automotive trim, a dash board and an air bag cover.

Assignees

• Basell Poliolefine Italia Srl

Inventors

• Fantinel Fabiana
• Willems Sander
• Grazzi Michele
• Pellegatti Giampaolo
• Rohrmann Jurgen
• Mihan Shahram

Classifications

• C08L2205/035

  containing four or more polymers in a blend · CPC title

• C08L23/12 Primary

  Polypropene · CPC title

• C08L2205/02

  containing two or more polymers of the same C08L -group · CPC title

• C08L23/16

  Ethylene-propylene or ethylene-propylene-diene copolymers · CPC title

• C08L23/0807

  with unsaturated hydrocarbons only containing four or more carbon atoms · CPC title