Mineral-filled polypropylene composition

Patent metadata

Field	Value
Publication number	US-9758657-B2
Application number	US-201414775488-A
Country	US
Kind code	B2
Filing date	Mar 10, 2014
Priority date	Mar 19, 2013
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

The present invention relates to low density polypropylene compositions for the production of molded articles, such as finished parts for the automotive industry.

First claim

What is claimed is:

1. A composition comprising:
(A) 15-60% by weight of one or more propylene-based components being selected from propylene homopolymers, propylene copolymers or combinations thereof, comprising a flexural modulus (ISO 178) higher than 1500 MPa, a melt flow rate (MFR) of 20-50 g/10 min and a PI higher than 10;
(B) 20-50% by weight of a heterophasic propylene polymer having a melt flow rate of 10-20 g/10 min comprising:
(B1) 50-90% by weight of a crystalline polypropylene having a solubility in xylene at room temperature lower than 5% by weight of the component (B1) and an MFR higher than 50 g/10 min;
(B2) 10-50% by weight of a copolymer of ethylene with at least one C 3 -C 10 alpha-olefin as comonomer such copolymer containing 40-60% by weight of ethylene and having a xylene solubility at room temperature higher than 70% by weight;

(D) 5-25% by weight of an ethylene-based plastomer or elastomer, having a hardness (Shore A, ASTM D-2240) value equal to or lower than 90 points, and a density lower than 0.890 g/cm 3 ;
(E) 10-15% by weight of talc; and
(F) 3-8% by weight of high-density polyethylene (HDPE);
wherein the composition comprises 1) a flexural modulus of greater than 1400 MPa; 2) a tensile modulus of greater than 1000 MPa: and 3) a density lower than 1 g/cm 3 ; and a sum of the percentage amounts of components (A)-(F) equals 100%.

2. The composition of claim 1 , wherein the flexural modulus determined in accordance with ISO 178 of the component (A) is higher than 2000 MPa and the PI of the component (A) is higher than 13.

3. The composition of claim 1 , wherein the melt flow rate MFR (230° C., 2.16 kg) value of component (B1) is higher than 70 g/10 min.

4. The composition of claim 1 , wherein component (E) has a high aspect ratio talc with lamellarity index equal to or higher than 2.8.

5. A molded article prepared from the composition of claim 1 .

6. The molded article of claim 5 , comprising a finished part for use in the automotive industry.

7. The molded article of claim 6 , wherein the finished part is selected from the group consisting of a dashboard, an instrument panel, an interior trim component and an exterior trim component.

Assignees

• Basell Polyolefine Italia S R L
• Basell Poliolefine Italia Srl

Inventors

• Rohrmann Jurgen
• Licht Erik Hans
• Ahrenberg Holger

Classifications

• C08L2207/02

  Heterophasic composition · CPC title

• C08J2323/14

  Copolymers of propene (C08J2323/16 takes precedence) · CPC title

• C08J2423/12

  Polypropene · CPC title

• C08L23/14 Primary

  Copolymers of propene (C08L23/16 takes precedence) · CPC title

• C08L23/12

  Polypropene · CPC title