Modified polypropylene composition and laminate using the same

Patent metadata

Field	Value
Publication number	US-9447267-B2
Application number	US-201113992566-A
Country	US
Kind code	B2
Filing date	Dec 7, 2011
Priority date	Dec 9, 2010
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

It is an object of the present invention to provide a modified polypropylene composition for forming laminates, which enables prevention of lowering of interlaminar bond strength even in the case where it is subjected to high-speed molding or subjected to stretch molding, and a laminate using the composition and having excellent interlaminar bond properties. The present invention relates to a modified polypropylene composition comprising a propylene-based polymer (A-1), 0 to 45% by weight of a propylene-based polymer (A-2), an ethylene/α-olefin copolymer (B) having a melt flow rate (MFR; ASTM D1238, 230° C., load of 2.16 kg) of 0.01 to 40 g/10 min and a density (ASTM D1505) of not more than 0.900 g/cm 3 , and a specific amount of modified polypropylene (C) a part or all of which has been graft-modified with an unsaturated carboxylic acid or a derivative thereof.

First claim

The invention claimed is:

1. A modified polypropylene composition comprising
60 to 85% by weight of an isotactic propylene-based polymer (A-1),
10 to 30% by weight of an ethylene/α-olefin copolymer (B) having a melt flow rate (MFR; ASTM D1238, 230° C., load of 2.16 kg) of 0.01 to 40 g/10 min, a density (ASTM D1505) of not more than 0.900 g/cm 3 and containing constituent units derived from ethylene in an amount of 55 to 95% by weight, and
0.01 to 10% by weight of modified polypropylene (C) all of which has been graft-modified with an unsaturated carboxylic acid or a derivative thereof [(A-1)+(B)+(C)=100% by weight],
wherein the propylene-based polymer (A-1) has the following properties:
[1] MFR (230° C., load of 2.16 kg) is 1 to 50 (g/10 min),
[2] the elution peak temperature based on TREF is not higher than 75° C., and the elution integrated value at 20° C. is less than 0.1% by weight, as measured by using o-dichlorobenzene as an eluent, and
[3] the melting point, as determined by DSC, is not higher than 135° C.

2. The modified polypropylene composition as claimed in claim 1 ,
wherein the propylene-based polymer (A-1) is a copolymer obtained by copolymerizing propylene and an α-olefin selected from the group consisting of ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene in the presence of a metallocene catalyst.

3. The modified polypropylene composition as claimed in claim 1 ,
wherein the melt flow rate (MFR; ASTM D1238, 230° C., load of 2.16 kg) of the propylene-based polymer (A-1) is 2 to 6 g/10 min.

4. A laminate comprising a 2-layer or 3-layer structure consisting of a composition layer composed of the modified polypropylene composition as claimed in claim 1 and a resin layer or resin layers provided on one surface or both surfaces of the composition layer.

5. The laminate as claimed in claim 4 ,
wherein the resin layer contains a layer composed of a polymer containing at least a monomer having a polar group.

6. A laminate comprising a layer (Z) composed of an ethylene/vinyl alcohol copolymer, a layer (Y) composed of the modified polypropylene composition as claimed in claim 1 and a layer (X) composed of unmodified polypropylene, said layers being laminated in this order.

7. A modified polypropylene composition comprising
25 to 85% by weight of an isotactic propylene-based polymer (A-1),
0 to 45% by weight of a propylene-based polymer (A-2),
10 to 30% by weight of an ethylene/α-olefin copolymer (B) having a melt flow rate (MFR; ASTM D1238, 230° C., load of 2.16 kg) of 0.01 to 40 g/10 min, a density (ASTM D1505) of not more than 0.900 g/cm 3 and containing constituent units derived from ethylene in an amount of 55 to 95% by weight, and
0.01 to 10% by weight of modified polypropylene (C) all of which has been graft-modified with an unsaturated carboxylic acid or a derivative thereof [(A-1)+(A-2)+(B)+(C)=100% by weight],
wherein the propylene-based polymer (A-1) has the following properties:
[1] MFR (230° C., load of 2.16 kg) is 1 to 50 (g/10 min),
[2] the elution peak temperature based on TREF is not higher than 75° C., and the elution integrated value at 20° C. is less than 0.1% by weight, as measured by using o-dichlorobenzene as an eluent, and
[3] the melting point, as determined by DSC, is not higher than 135° C., and
the propylene-based polymer (A-2) has an elution peak temperature based on TREF of higher than 75° C.

8. The modified polypropylene composition as claimed in claim 7 ,
wherein the propylene-based polymer (A-1) is a copolymer obtained by copolymerizing propylene and an α-olefin selected from the group consisting of ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene in the presence of a metallocene catalyst.

9. The modified polypropylene composition as claimed in claim 7 ,
wherein the melt flow rate (MFR; ASTM D1238, 230° C., load of 2.16 kg) of the propylene-based polymer (A-1) is 2 to 6 g/10 min.

10. A laminate comprising a 2-layer or 3-layer structure consisting of a composition layer composed of the modified polypropylene composition as claimed in claim 7 and a resin layer or resin layers provided on one surface or both surfaces of the composition layer.

11. The laminate as claimed in claim 10 ,
wherein the resin layer contains a layer composed of a polymer containing at least a monomer having a polar group.

12. A laminate comprising a layer (Z) composed of an ethylene/vinyl alcohol copolymer, a layer (Y) composed of the modified polypropylene composition as claimed in claim 7 and a layer (X) composed of unmodified polypropylene, said layers being laminated in this order.

Assignees

• Matsumoto Hironori
• Uosaki Hirotaka
• Kitahara Koji
• Sawada Yuji
• Mitsui Chemicals Inc

Inventors

• Matsumoto Hironori
• Uosaki Hirotaka
• Kitahara Koji
• Sawada Yuji

Classifications

• C08L23/0815

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

• C08L23/10

  Homopolymers or copolymers of propene · CPC title

• B32B27/327

  comprising polyolefins obtained by a metallocene or single-site catalyst · CPC title

• Y10T428/31938

  Polymer of monoethylenically unsaturated hydrocarbon · CPC title

• C08L23/12 Primary

  Polypropene · CPC title