Fiber reinforced polypropylene composition

Patent metadata

Field	Value
Publication number	US-11912849-B2
Application number	US-201816763014-A
Country	US
Kind code	B2
Filing date	Dec 4, 2018
Priority date	Dec 5, 2017
Publication date	Feb 27, 2024
Grant date	Feb 27, 2024

Abstract

The present invention is directed to granules comprising a fiber reinforced composition (C), said composition comprising a propylene polymer (PP), an elastomeric ethylene copolymer (E) and long fibers (LF).

First claim

The invention claimed is:

1. Granules comprising a fiber reinforced composition (C), comprising
i) an at least bimodal propylene polymer (PP), wherein the propylene polymer (PP) has a xylene cold soluble (XCS) content of below 3.1 wt.-%,
ii) an elastomeric ethylene copolymer (E) which is a copolymer of ethylene and a C 4 -C 10 α-olefin,
iii) an adhesion promoter (AP), and
iv) long fibers (LF),
wherein said fiber reinforced composition (C) fulfils in-equation (Ia)

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w
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P
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P

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w
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E
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Ia
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wherein w(PP) is the weight fraction [in wt.-%] of the propylene polymer (PP), based on the overall weight of the fiber reinforced composition (C), and w(E) is the weight fraction [in wt.-%] of the elastomeric ethylene copolymer (E), based on the overall weight of the fiber reinforced composition (C);
wherein the propylene polymer (PP) comprises
i′) a first propylene polymer (PP1) having a melt flow rate MFR 2 (230° C., 2.16 kg) determined according to ISO 1133 of at least 100 g/10 min, and
ii′) a second propylene polymer (PP2) having a melt flow rate MFR 2 (230° C., 2.16 kg) determined according to ISO 1133 below 150 g/10 min,
with the proviso that the first polypropylene (PP1) has a higher melt flow rate MFR 2 (230° C., 2.16 kg) determined according to ISO 1133 than the second propylene polymer (PP2), and
wherein the granules comprise
a) an inner layer comprising the long fibers (LF) and the first propylene polymer (PP1), and
b) an outer layer coated onto the core comprising the second propylene polymer (PP2) and the elastomeric ethylene copolymer (E),
wherein the inner layer and/or the outer layer further comprises the adhesion promoter (AP).

2. The granules according to claim 1 , wherein the fiber reinforced composition (C) comprises
i) 30.0 to 80.0 wt.-% of the propylene polymer (PP),
ii) 2.0 to 12.0 wt.-% of the elastomeric ethylene copolymer (E),
iii) 0.1 to 5.0 wt.-% of the adhesion promoter (AP), and
iv) 10.0 to 60.0 wt.-% of the long fibers (LF),
based on the overall weight of the fiber reinforced composition (C).

3. The granules according to claim 1 , wherein the adhesion promoter (AP) is a polar modified polypropylene (PM-PP), which is a propylene homo- or copolymer grafted with maleic anhydride having a melt flow rate MFR (190° C., 2.16 kg) determined according to ISO 1133 of at least 50.0 g/10 min.

4. The granules according to claim 1 , wherein the elastomeric ethylene copolymer (E) has a melt flow rate MFR (190° C., 2.16 kg) determined according to ISO 1133 of at least 25.0 g/10 min.

5. The granules according to claim 1 , wherein the elastomeric ethylene copolymer (E) has a comonomer content of 2.0 to 25.0 mol-%.

6. The granules according to claim 1 , wherein the elastomeric ethylene copolymer (E) has a density below 0.900 g/cm 3 .

7. The granules according to claim 1 , wherein the elastomeric ethylene copolymer (E) is a copolymer of ethylene and 1-octene.

8. The granules according to claim 1 , wherein the propylene polymer (PP) is a propylene homopolymer.

9. The granules according to claim 1 , wherein the long fibers (LF) are selected from the group consisting of glass fibers, metal fibers, ceramic fibers, carbon fibers, and graphite fibers.

10. The granules according to claim 9 , wherein the long fibers (LF) are long glass fibres (LGF).

11. The granules according to claim 1 , wherein the long fibers have a diameter of at least 10 μm.

12. The granules according to claim 1 , wherein the second propylene polymer (PP2) is at least bimodal.

13. The granules according to claim 1 , wherein said granules are obtained by
a) contacting the long fibers (LF) with a melt of the first polypropylene (PP1) and the adhesion promoter (AP), thereby obtaining impregnated fibers,
b) contacting the impregnated fibers obtained in step a) with a melt of the second polypropylene (PP2) and the elastomeric ethylene copolymer (E), thereby obtaining a strand of fiber reinforced polypropylene, and
c) cutting the strand of fiber reinforced polypropylene obtained in step b) into granules.

Assignees

• Borealis Ag

Inventors

• Jerabek Michael
• Stockreiter Wolfgang
• Lummerstorfer Thomas

Classifications

• C08L23/12 Primary

  Polypropene · CPC title

• C08J3/126

  Polymer particles coated by polymer, e.g. core shell structures · CPC title

• C08K7/14

  Glass · CPC title

• C08L23/0815

  with aliphatic 1-olefins containing one carbon-to-carbon double bond · CPC title

• C08L51/003

  grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds (C08L51/04, C08L51/06 take precedence) · CPC title