Polypropylene composition for foaming

Patent metadata

Field	Value
Publication number	US-9587079-B2
Application number	US-201214355476-A
Country	US
Kind code	B2
Filing date	Oct 16, 2012
Priority date	Nov 2, 2011
Publication date	Mar 7, 2017
Grant date	Mar 7, 2017

Abstract

The present invention relates to a new polypropylene composition for molded articles, such as finished parts for the automotive industry. A composition comprising: (A) from 40 to 85% by weight of a first propylene-based component being selected from propylene homopolymers, propylene copolymers and heterophasic propylene polymer, such first propylene-based component having a flexural modulus higher than 800 MPa; (B) from 5 to 20% by weight of a second propylene-based component being a heterophasic propylene polymer comprising: (B1) from 20 to 90% by weight of a crystalline polypropylene, and (B2) from 10 to 80% by weight of a copolymer of ethylene and at least one C 3 -C 10 alpha-olefin, such copolymer containing from 10 to 70% by weight of ethylene, being soluble in xylene at room temperature, and having an intrinsic viscosity in tetrahydronaphtalene at 135° C. of higher than 3.5 dl/g; and (C) from 10 to 40% by weight of glass fibers.

First claim

What is claimed is:

1. A composition comprising:
(A)40-85% by weight of a first propylene-based component being selected from propylene homopolymers, propylene copolymers and heterophasic propylene polymer, such first propylene-based component having a flexural modulus determined in accordance with ISO 178 higher than 800 MPa;
(B) 5-20% by weight of a second propylene-based component being a heterophasic propylene polymer comprising:
(B1) 50% -90% of a crystalline polypropylene component comprising 25%-75% of a fraction a I having a melt flow rate MFR I of 0.5-10 g/10 min, and 25%-75% of a fraction of a II having a melt flow rate MFR II such that a ratio MFR II /MFR I is from 50-1000; and wherein fractions a I and a II are independently selected from the group consisting of a propylene homopolymer, a random copolymer of propylene containing up to 8% of ethylene, and a random copolymer of propylene containing up to 8% of at least one C 4 -C 10 alpha-olefin; and
(B2) 10%-50% of a copolymer component of ethylene and at least one C 3 -C 10 alpha-olefin, the copolymer containing 15-50% of ethylene, said copolymer being soluble in xylene at about 25° C, and having an intrinsic viscosity in tetrahydronaphthalene at 135° C. of 5-8 dl/g; and
(C) 10%-40% by weight of glass fibers having a length from 0.3-1.0 mm and a diameter from 10-15μm,
wherein said composition has a melt flow rate value (ISO 1133-230° C., 2.16 kg) from 70-120 g/10 min.

2. The composition of claim 1 , wherein (B2) further comprises a diene.

3. A foamed article prepared from the composition of claim 1 .

4. The foamed article of claim 3 , selected from a dashboard and an instrument panel.

5. A vehicle comprising the foamed article of claim 4 .

Assignees

• Basell Poliolefine Italia Srl

Inventors

• Langenfelder Dieter
• Rohrmann Jurgen

Classifications

• C08L23/12 Primary

  Polypropene · CPC title

• C08L23/16

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

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title

• C08K7/14

  Glass · CPC title

• C08L2207/02

  Heterophasic composition · CPC title