Highly saturated nitrile rubber composition and cross-linked rubber

Patent metadata

Field	Value
Publication number	US-10280298-B2
Application number	US-201214004172-A
Country	US
Kind code	B2
Filing date	Mar 29, 2012
Priority date	Mar 31, 2011
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A highly saturated nitrile rubber composition containing a carboxyl group-containing highly saturated nitrile rubber (A1) which contains α,β-ethylenically unsaturated nitrile monomer units 15 to 60 wt % and α,β-ethylenically unsaturated dicarboxylic acid monoester monomer units 1 to 60 wt % and has an iodine value of 120 or less, a highly saturated nitrile rubber (A2) which contains α,β-ethylenically unsaturated nitrile monomer units 15 to 60 wt %, has a content of the α,β-ethylenically unsaturated dicarboxylic acid monoester monomer units of 0.9 wt % or less, and has an iodine value of 120 or less, and a polyamide resin (B), a content ratio of the carboxyl group-containing highly saturated nitrile rubber (A1) and the highly saturated nitrile rubber (A2) being a weight ratio of “carboxyl group-containing highly saturated nitrile rubber (A1):highly saturated nitrile rubber (A2)” of 2:98 to 98:2, is provided.

First claim

The invention claimed is:

1. A cross-linked rubber obtained by cross-linking a cross-linkable nitrile rubber composition
the cross-linkable nitrile rubber composition containing:
a carboxyl group-containing nitrile rubber (A1) which contains α,β-ethylenically unsaturated nitrile monomer units 15 to 60 wt % and α,β-ethylenically unsaturated dicarboxylic acid monoester monomer units 2 to 20 wt % and has an iodine value of 120 or less,
a nitrile rubber (A2) which contains α,β-ethylenically unsaturated nitrile monomer units 15 to 60 wt %, has a content of the α,β-ethylenically unsaturated dicarboxylic acid monoester monomer units of 0.9 wt % or less, and has an iodine value of 120 or less,
a polyamide resin (B), and
an organic peroxide cross-linking agent (C), wherein
a content ratio of said carboxyl group-containing nitrile rubber (A1) and said nitrile rubber (A2) in the cross-linkable nitrile rubber composition is a weight ratio of “carboxyl group-containing nitrile rubber (A1):nitrile rubber (A2)” of 5:95 to 40:60, and
the tensile strength at 100° C. of the cross-linked rubber is 13.1 MPa or more.

2. The cross-linked rubber as set forth in claim 1 wherein said polyamide resin (B) has a melting point of 100 to 300° C.

3. The cross-linked rubber as set forth in claim 1 wherein the α,β-ethylenically unsaturated dicarboxylic acid monoester monomer units of said carboxyl group-containing nitrile rubber (A1) are monoalkyl ester units of maleic acid.

4. The cross-linked rubber as set forth in claim 1 wherein a content of said polyamide resin (B) with respect to a total amount of said carboxyl group-containing nitrile rubber (A1) and said nitrile rubber (A2) is, by weight ratio of “total amount of carboxyl group-containing nitrile rubber (A1) and nitrile rubber (A2):content of polyamide resin (B)”, 95:5 to 50:50.

5. The cross-linked rubber as set forth in claim 1 wherein the cross-linkable nitrile rubber composition is obtained by kneading said carboxyl group-containing nitrile rubber (A1), said nitrile rubber (A2), and said polyamide resin (B) at a temperature of 200° C. or more.

6. The cross-linked rubber as set forth in claim 5 wherein the cross-linkable nitrile rubber composition is obtained by kneading said carboxyl group-containing nitrile rubber (A1), said nitrile rubber (A2), and said polyamide resin (B) at a temperature of 200° C. or more by a twin screw extruder.

7. The cross-linked rubber as set forth in claim 1 which is a seal, gasket, belt, or hose.

8. A method of production of the cross-linked rubber as set forth in claim 1 comprising
kneading said carboxyl group-containing nitrile rubber (A1), said nitrile rubber (A2), and said polyamide resin (B) at a temperature of 200° C. or more so as to obtain a nitrile rubber composition,
blending an organic peroxide cross-linking agent (C) into the nitrile rubber composition so as to obtain a cross-linkable nitrile rubber composition, and
cross-linking the cross-linkable nitrile rubber composition.

9. The method of production of the cross-linked rubber as set forth in claim 8 wherein the kneading said carboxyl group-containing nitrile rubber (A1), said nitrile rubber (A2), and said polyamide resin (B) is performed by using a twin screw extruder.

10. The cross-linked rubber as set forth in claim 1 wherein the elongation at 100° C. of the cross-linked rubber is 140% or more.

Assignees

• Nakashima Tomonori
• Sakamoto Masato
• Zeon Corp

Inventors

• Nakashima Tomonori
• Sakamoto Masato

Classifications

• Y10T428/1386

  Natural or synthetic rubber or rubber-like compound containing · CPC title

• C08L2312/00

  Crosslinking · CPC title

• C08L77/00

  Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain (of polyhydrazides C08L79/06; of polyamideimides or polyamide acids C08L79/08); Compositions of derivatives of such polymers · CPC title

• C08L13/00

  Compositions of rubbers containing carboxyl groups · CPC title

• C08L77/02

  Polyamides derived from omega-amino carboxylic acids or from lactams thereof (C08L77/10 takes precedence) · CPC title