NITRILE GROUP-CONTAINING COPOLYMER RUBBER

• US 20200131293A1
• Filed: 02/23/2018
• Published: 04/30/2020
• Est. Priority Date: 03/17/2017
• Status: Abandoned Application

• Current Assignee: ZEON Corporation
• Original Assignee: ZEON Corporation
• Inventors: SHIONO, Atsuhiro
• Application Number:
  US16/493,270
• Publication Number:
  US 20200131293A1
• Time in Patent Office: Days
• CPC Class Codes: C08C 1/14 Coagulation
• CPC Class Codes: C08C 19/02 Hydrogenation
• CPC Class Codes: C08C 19/22 Incorporating nitrogen atoms into the molecule
• CPC Class Codes: C08F 2/24 with the aid of emulsifying agents
• CPC Class Codes: C08F 2/38 Polymerisation using regulators, e.g. chain terminating agents , e.g. telomerisation
• CPC Class Codes: C08F 220/1804 C4-(meth)acrylate, e.g. butyl (meth)acrylate, isobutyl (meth)acrylate or tert-butyl (meth)acrylate
• CPC Class Codes: C08F 220/281 and containing only one oxygen, e.g. furfuryl (meth)acrylate or 2-methoxyethyl (meth)acrylate
• CPC Class Codes: C08F 220/44 Acrylonitrile
• CPC Class Codes: C08F 222/16 Esters having free carboxylic acid groups , e.g. monoalkyl maleates or fumarates
• CPC Class Codes: C08F 236/06 Butadiene
• CPC Class Codes: C08F 236/14 containing elements other than carbon and hydrogen
• CPC Class Codes: C08K 5/0025 Crosslinking or vulcanising agents; including accelerators
• CPC Class Codes: C08K 5/205 Compounds containing groups, e.g. carbamates
• CPC Class Codes: C08K 5/3465 condensed with carbocyclic rings
• CPC Class Codes: C08L 13/00 Compositions of rubbers containing carboxyl groups
• CPC Class Codes: C08L 15/005 Hydrogenated nitrile rubber

Abstract

A nitrile group-containing copolymer rubber including 10 to 60 wt % of an α,β-ethylenically unsaturated nitrile monomer unit and 1 to 60 wt % of an α,β-ethylenically unsaturated dicarboxylic acid monoester monomer unit, and having an iodine value of 120 or less, wherein a processability index Ipro (Ipro=CC×SA) is 0.0030 or less, where the processability index Ipro is the product of the carboxyl group content CC, which is the number of moles of carboxyl groups per 100 g of nitrile group-containing copolymer rubber, and the absorbance area SA of a carboxylic anhydride group determined by infrared spectroscopy.

Claims

1. A nitrile group-containing copolymer rubber comprising 10 to 60 wt % of an α

,β

-ethylenically unsaturated nitrile monomer unit and 1 to 60 wt % of an α

,β

-ethylenically unsaturated dicarboxylic acid monoester monomer unit, and having an iodine value of 120 or less,

wherein a processability index I_pro (I_pro=C_C×

S_A) is 0.0030 or less, where the processability index I_pro is the product of the carboxyl group content C_C, which is the number of moles of carboxyl groups per 100 g of nitrile group-containing copolymer rubber, and the absorbance area S_A of a carboxylic anhydride group determined by infrared spectroscopy.

2. The nitrile group-containing copolymer rubber according to claim 1, wherein a conjugated diene monomer unit is contained in an amount of 20 to 89 wt %.

3. The nitrile group-containing copolymer rubber according to claim 1, wherein a content of the α

,β

-ethylenically unsaturated dicarboxylic acid monoester monomer unit is 1 to 10 wt %.

4. The nitrile group-containing copolymer rubber according to claim 1, wherein the α

,β

-ethylenically unsaturated dicarboxylic acid monoester monomer unit is at least one selected from the group consisting of a mono-n-butyl maleate unit, a mono-n-butyl fumarate unit, and a monocyclohexyl fumarate unit.

5. A cross-linkable rubber composition comprising the nitrile group-containing copolymer rubber according to claim 1 and a cross-linking agent.

6. The cross-linkable rubber composition according to claim 5, further comprising a basic cross-linking accelerator having a cyclic amidine structure.

7. A cross-linked rubber prepared by cross-linking the cross-linkable rubber composition according to claim 5.