JP2023006576A - Crosslinkable rubber composition and crosslinked rubber - Google Patents

Abstract

To provide a crosslinkable rubber composition that effectively prevents a deterioration of mechanical properties and a change in volume under acidic and alkaline environments, and is suitable for contact with acid or alkali.SOLUTION: A crosslinkable rubber composition contains hydrogenated nitrile group-containing rubber and an amine crosslinker and is used to be in contact with acid or alkali.SELECTED DRAWING: None

Description

The present invention provides a crosslinkable rubber composition in which deterioration in mechanical properties and volume change in acidic and alkaline environments are effectively suppressed, and which can be suitably used for applications in contact with acid or alkali. It relates to a rubber cross-linked product obtained using a cross-linkable rubber composition.

Hydrogenated nitrile group-containing rubber represented by hydrogenated acrylonitrile-butadiene copolymer rubber is a general nitrile group with many carbon-carbon unsaturated bonds in the main chain structure, such as acrylonitrile-butadiene copolymer rubber. Compared to the contained rubber, it is excellent in heat resistance, oil resistance, ozone resistance, etc., so it is suitably used as rubber parts such as automobile seals, hoses, and tubes.

For example, in Patent Document 1, a rubber cross-linked product obtained by cross-linking a rubber composition containing a hydrogenated nitrile group-containing rubber and a peroxide cross-linking agent is used for blow-by gas hoses and EGR (exhaust gas recirculation) hoses. A technique applied to the application is disclosed.

Here, the blow-by gas hose is a hose for circulating blow-by gas, which is aggressive leakage gas generated in the crank chamber of the engine. The blow-by gas and EGR gas to be circulated by these hoses usually contain acidic condensed water and its vapor. In addition, a urea SCR system has been introduced in order to treat NO _x generated in diesel engines, and in order to suppress the amount of ammonia generated in the treatment process, exhaust gas containing ammonia after urea SCR treatment is also considered to be returned into the combustion chamber as EGR gas. Since blow-by gas and EGR gas contain acids and alkalis, blow-by gas hoses and EGR hoses are exposed to acids and alkalis. is required to have sufficient resistance to acids and alkalis, specifically, to sufficiently suppress deterioration of mechanical properties and change in volume in acidic and alkaline environments.

On the other hand, the rubber composition disclosed in Patent Document 1 and the rubber cross-linked product obtained by crosslinking the same do not necessarily have sufficient resistance to acids and alkalis, and therefore further improvements have been desired.

WO2019/034572

The present invention has been made in view of such actual circumstances, and the deterioration of mechanical properties and volume change in acidic and alkaline environments are effectively suppressed, and it is suitable for use in applications that come into contact with acids or alkalis. An object of the present invention is to provide a crosslinkable rubber composition that can be
Another object of the present invention is to provide a cross-linked rubber obtained by using such a cross-linkable rubber composition.

As a result of intensive research to achieve the above object, the present inventors have found that a cross-linkable rubber composition containing a hydrogenated nitrile group-containing rubber and an amine-based cross-linking agent can be used in both acidic and alkaline environments. The inventors have found that the decrease in mechanical properties and the volume change in the material can be effectively suppressed, and that it can be suitably used for applications that come into contact with acids or alkalis, and have completed the present invention.

That is, according to the present invention, there is provided a crosslinkable rubber composition containing a hydrogenated nitrile group-containing rubber and an amine-based crosslinker and used for applications that come into contact with acid or alkali.
The crosslinkable rubber composition of the present invention is preferably used for applications that come into contact with blow-by gas or EGR gas.

Further, according to the present invention, there is provided a cross-linked rubber obtained by cross-linking the cross-linkable rubber composition, which is used for applications that come into contact with acid or alkali.
The cross-linked rubber product of the present invention is preferably used for applications that come into contact with blow-by gas or EGR gas.

ADVANTAGE OF THE INVENTION According to the present invention, a crosslinkable rubber composition in which deterioration in mechanical properties and volume change in an acidic environment and an alkaline environment are effectively suppressed, and which can be suitably used for applications in contact with acid or alkali; It is possible to provide a rubber cross-linked product obtained by using such a cross-linkable rubber composition.

<Crosslinkable rubber composition>
The crosslinkable rubber composition of the present invention is a rubber composition containing a hydrogenated nitrile group-containing rubber and an amine cross-linking agent, and is used for applications in contact with acid or alkali.

The hydrogenated nitrile group-containing rubber used in the present invention is obtained by copolymerizing an α,β-ethylenically unsaturated nitrile monomer and a conjugated diene monomer and hydrogenating the resulting copolymer. It is a rubber that can be

The α,β-ethylenically unsaturated nitrile monomer is not limited as long as it is an α,β-ethylenically unsaturated compound having a nitrile group. Halogenoacrylonitrile; alpha-alkyl acrylonitrile such as methacrylonitrile; acrylonitrile and methacrylonitrile are preferred; The α,β-ethylenically unsaturated nitrile monomers may be used singly or in combination.

The content of α,β-ethylenically unsaturated nitrile monomer units in the hydrogenated nitrile group-containing rubber used in the present invention is preferably 5 to 60% by weight, more preferably 10 to 52% by weight, More preferably 15 to 44% by weight. By setting the content of the α,β-ethylenically unsaturated nitrile monomer unit within the above range, the resulting cross-linked rubber is further suppressed in deterioration of mechanical properties and volume change in acidic and alkaline environments. can be assumed.

As the conjugated diene monomer, a conjugated diene monomer having 4 to 6 carbon atoms such as 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene and chloroprene is preferable. , 1,3-butadiene and isoprene are more preferred, and 1,3-butadiene is particularly preferred. Conjugated diene monomers may be used singly or in combination.

The content of conjugated diene monomer units (including hydrogenated portions) in the hydrogenated nitrile group-containing rubber used in the present invention is 20 to 90% by weight based on the total monomer units. , more preferably 25 to 80% by weight, more preferably 30 to 70% by weight. By setting the content of the conjugated diene monomer unit within the above range, the resulting crosslinked rubber can have excellent rubber elasticity while maintaining good heat resistance and chemical resistance stability.

The hydrogenated nitrile group-containing rubber used in the present invention is obtained by copolymerizing an α,β-ethylenically unsaturated nitrile monomer, a conjugated diene monomer, and a carboxyl group-containing monomer. may

The carboxyl group-containing monomer is not particularly limited as long as it is a monomer having one or more unsubstituted (free) carboxyl groups that are not esterified, etc. For example, α,β-ethylenically unsaturated Examples include monocarboxylic acid monomers, α,β-ethylenically unsaturated polycarboxylic acid monomers, and α,β-ethylenically unsaturated dicarboxylic acid monoester monomers. The carboxyl group-containing monomers also include monomers in which the carboxyl group of these monomers forms a carboxylate. Furthermore, anhydrides of α,β-ethylenically unsaturated polycarboxylic acids can also be used as carboxyl group-containing monomers because they cleave the acid anhydride groups to form carboxyl groups after copolymerization.

The α,β-ethylenically unsaturated monocarboxylic acid monomers include acrylic acid, methacrylic acid, ethylacrylic acid, crotonic acid, cinnamic acid and the like.

Examples of α,β-ethylenically unsaturated polycarboxylic acid monomers include butenedioic acids such as fumaric acid and maleic acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, allylmalonic acid, and teraconic acid. Examples of anhydrides of α,β-unsaturated polycarboxylic acids include maleic anhydride, itaconic anhydride, and citraconic anhydride.

Examples of α,β-ethylenically unsaturated dicarboxylic acid monoester monomers include maleic acid monoalkyl esters such as monomethyl maleate, monoethyl maleate, monopropyl maleate, and mono-n-butyl maleate; monocyclopentyl maleate; Maleic acid monocycloalkyl esters such as monocyclohexyl maleate and monocycloheptyl maleate; maleic acid monoalkylcycloalkyl esters such as monomethylcyclopentyl maleate and monoethylcyclohexyl maleate; monomethyl fumarate, monoethyl fumarate, and monofumarate Fumarate monoalkyl esters such as propyl and mono-n-butyl fumarate; Fumarate monocycloalkyl esters such as monocyclopentyl fumarate, monocyclohexyl fumarate, monocycloheptyl fumarate; monomethylcyclopentyl fumarate, monoethylcyclohexyl fumarate Citraconic acid monoalkyl esters such as fumaric acid monoalkyl cycloalkyl esters such as fumaric acid monomethyl citraconate, citraconic acid monoethyl, citraconic acid monopropyl, citraconic acid mono-n-butyl citraconic acid monoalkyl esters; citraconic acid monocyclopentyl, citraconic monocyclohexyl citraconic acid mono Citraconic acid monocycloalkyl esters such as cycloheptyl; citraconic acid monoalkylcycloalkyl esters such as monomethylcyclopentyl citraconate, monoethylcyclohexyl citraconate; monomethyl itaconate, monoethyl itaconate, monopropyl itaconate, mono-n-butyl itaconate monoalkyl itaconate such as; monocycloalkyl itaconate such as monocyclopentyl itaconate, monocyclohexyl itaconate, monocycloheptyl itaconate; monoalkylcycloalkyl itaconate such as monomethylcyclopentyl itaconate, monoethylcyclohexyl itaconate ester; and the like.

A carboxyl group-containing monomer may be used singly or in combination. Among these, α,β-ethylenically unsaturated monocarboxylic acid monomers and α,β-ethylenically unsaturated dicarboxylic acid monoester monomers are preferred, and acrylic acid, methacrylic acid, maleic acid monoalkyl esters, fumaric acid Acid monoalkyl esters are more preferred.

The content of the carboxyl group-containing monomer units in the hydrogenated nitrile group-containing rubber used in the present invention is 0.5 to 12% by weight, more preferably 1 to 10% by weight, based on the total monomer units. % by weight, more preferably 2 to 8% by weight.

In addition, the hydrogenated nitrile group-containing rubber used in the present invention includes an α,β-ethylenically unsaturated nitrile monomer, a conjugated diene monomer, and optionally a carboxyl group-containing monomer. Alternatively, it may be obtained by copolymerizing an α,β-ethylenically unsaturated monocarboxylic acid ester monomer.

The α,β-ethylenically unsaturated monocarboxylic acid ester monomer is not particularly limited, but examples include α,β-ethylenically unsaturated monocarboxylic acid alkyl ester monomers, α,β-ethylenically unsaturated Examples include monocarboxylic acid alkoxyalkyl ester monomers.

The alkyl ester monomer of α,β-ethylenically unsaturated monocarboxylic acid preferably has an alkyl group having 3 to 10 carbon atoms as an alkyl group, and an alkyl group having 3 to 8 carbon atoms. and more preferably an alkyl group having 4 to 6 carbon atoms.

Specific examples of α,β-ethylenically unsaturated monocarboxylic acid alkyl ester monomers include methyl acrylate, ethyl acrylate, propyl acrylate, isobutyl acrylate, n-butyl acrylate, n-pentyl acrylate, acrylic acid alkyl ester monomers such as 2-ethylhexyl acrylate and n-dodecyl acrylate; acrylic acid cycloalkyl ester monomers such as cyclopentyl acrylate and cyclohexyl acrylate; methyl cyclopentyl acrylate, ethyl cyclopentyl acrylate, acrylic acrylic acid alkyl cycloalkyl ester monomers such as methyl cyclohexyl acid; methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, n-pentyl methacrylate, and n-octyl methacrylate Monomers; cycloalkyl methacrylate monomers such as cyclopentyl methacrylate, cyclohexyl methacrylate and cyclopentyl methacrylate; alkyl cycloalkyl methacrylate monomers such as methylcyclopentyl methacrylate, ethylcyclopentyl methacrylate and methylcyclohexyl methacrylate crotonate alkyl ester monomers such as propyl crotonate, n-butyl crotonate and 2-ethylhexyl crotonate; crotonate cycloalkyl ester monomers such as cyclopentyl crotonate, cyclohexyl crotonate and cyclooctyl crotonate; crotonate alkylcycloalkyl ester monomers such as methylcyclopentyl crotonate and methylcyclohexyl crotonate;

Further, the α,β-ethylenically unsaturated monocarboxylic acid alkoxyalkyl ester monomer preferably has an alkoxyalkyl group having 2 to 8 carbon atoms as an alkoxyalkyl group, and preferably has 2 to 6 carbon atoms. More preferably, it has an alkoxyalkyl group having from 2 to 4 carbon atoms.

Specific examples of α,β-ethylenically unsaturated monocarboxylic acid alkoxyalkyl ester monomers include methoxymethyl acrylate, methoxyethyl acrylate, methoxybutyl acrylate, ethoxymethyl acrylate, ethoxyethyl acrylate, and acrylic acid. Ethoxypropyl, ethoxydodecyl acrylate, n-propoxyethyl acrylate, i-propoxyethyl acrylate, n-butoxyethyl acrylate, i-butoxyethyl acrylate, t-butoxyethyl acrylate, methoxypropyl acrylate, acrylic acid alkoxyalkyl ester monomers such as methoxybutyl; methoxymethyl methacrylate, methoxyethyl methacrylate, methoxybutyl methacrylate, ethoxymethyl methacrylate, ethoxyethyl methacrylate, ethoxypentyl methacrylate, n-propoxyethyl methacrylate, i-propoxyethyl methacrylate, n-butoxyethyl methacrylate, i-butoxyethyl methacrylate, t-butoxyethyl methacrylate, methoxypropyl methacrylate, methoxybutyl methacrylate, methoxy-polyethylene glycol (meth)acrylate, methoxy-polyethylene methacrylic acid alkoxyalkyl ester monomers such as glycol (meth)acrylate; and the like.

Examples of α,β-ethylenically unsaturated monocarboxylic acid ester monomers include α-cyanoethyl acrylate, α-cyanoethyl methacrylate, α-cyanoethyl methacrylate, and cyanoalkyl groups having 2 to 12 carbon atoms (meta ) acrylic acid ester; (meth) acrylic acid ester having a hydroxyalkyl group having 1 to 12 carbon atoms such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate; trifluoroethyl acrylate , a (meth)acrylic acid ester having a fluoroalkyl group of 1 to 12 carbon atoms such as tetrafluoropropyl methacrylate; and the like can also be used.

Among these α,β-ethylenically unsaturated monocarboxylic acid ester monomers, α,β-ethylenically unsaturated monocarboxylic acid alkyl ester monomers, α,β-ethylenically unsaturated monocarboxylic acid alkoxyalkyl Ester monomers are preferred, and acrylic acid alkyl ester monomers and acrylic acid alkoxyalkyl ester monomers are more preferred. Two or more of these α,β-ethylenically unsaturated monocarboxylic acid ester monomers may be used in combination.

The content of α,β-ethylenically unsaturated monocarboxylic acid ester monomer units in the hydrogenated nitrile group-containing rubber used in the present invention is 12 to 50% by weight based on the total monomer units. , more preferably 15 to 45% by weight, more preferably 18 to 40% by weight.

The hydrogenated nitrile group-containing rubber used in the present invention includes an α,β-ethylenically unsaturated nitrile monomer, a conjugated diene monomer, and optionally a carboxyl group-containing monomer and/or Alternatively, in addition to the α,β-ethylenically unsaturated monocarboxylic acid ester monomers, other monomers copolymerizable therewith may be copolymerized. Such other monomers include α,β-ethylenically unsaturated dicarboxylic acid diester monomers, ethylene, α-olefin monomers, aromatic vinyl monomers, fluorine-containing vinyl monomers, co- A polymerizable antioxidant etc. are illustrated.

Examples of α,β-ethylenically unsaturated dicarboxylic acid diester monomers include dialkyl maleates such as dimethyl maleate and di-n-butyl maleate having alkyl groups of 1 to 18 carbon atoms; fumaric acid; Dialkyl fumarate esters such as dimethyl and di-n-butyl fumarate, in which the alkyl group has 1 to 18 carbon atoms; Dicycloalkyl maleate esters such as dicyclopentyl maleate and dicyclohexyl maleate, which are cycloalkyl dicycloalkyl fumarate esters such as dicyclopentyl fumarate and dicyclohexyl fumarate, in which the cycloalkyl group has 4 to 16 carbon atoms; dimethyl itaconate, di-itaconate Dialkyl itaconic acid esters such as n-butyl having 1 to 18 carbon atoms in the alkyl group: Dicycloalkyl itaconic esters such as dicyclohexyl itaconate having 4 to 16 carbon atoms in the cycloalkyl group ; and the like.

The α-olefin monomer preferably has 3 to 12 carbon atoms, such as propylene, 1-butene, 4-methyl-1-pentene, 1-hexene and 1-octene.

Examples of aromatic vinyl monomers include styrene, α-methylstyrene, vinylpyridine and the like.

Fluorine-containing vinyl monomers include fluoroethyl vinyl ether, fluoropropyl vinyl ether, o-trifluoromethylstyrene, vinyl pentafluorobenzoate, difluoroethylene and tetrafluoroethylene.

Copolymerizable antioxidants include N-(4-anilinophenyl) acrylamide, N-(4-anilinophenyl) methacrylamide, N-(4-anilinophenyl) cinnamamide, N-(4-anilino phenyl)crotonamide, N-phenyl-4-(3-vinylbenzyloxy)aniline, N-phenyl-4-(4-vinylbenzyloxy)aniline and the like.

These other copolymerizable monomers may be used in combination of multiple types. The content of other monomer units in the hydrogenated nitrile group-containing rubber used in the present invention is preferably 50% by weight or less, more preferably 30% by weight or less, based on the total monomer units. Preferably, it is 10% by weight or less.

The iodine value of the hydrogenated nitrile group-containing rubber used in the present invention is preferably 120 or less, more preferably 80 or less, still more preferably 50 or less, still more preferably 30 or less, particularly preferably 20 or less, most preferably 12 or less. By setting the iodine value of the hydrogenated nitrile group-containing rubber within the above range, the obtained crosslinked rubber can be made to have a more suppressed decrease in mechanical properties and volume change in acidic and alkaline environments. .

Polymer Mooney viscosity (ML1+4, 100°C) of the hydrogenated nitrile group-containing rubber used in the present invention is preferably 10 to 200, more preferably 15 to 150, still more preferably 15 to 100, and particularly preferably 30 to 80. be. By setting the polymer Mooney viscosity of the hydrogenated nitrile group-containing rubber to the above range, the mechanical properties of the resulting crosslinked rubber are further enhanced while maintaining good processability of the rubber composition when made into a rubber composition. be able to.

As the hydrogenated nitrile rubber used in the present invention, for example, Zetpol (registered trademark) manufactured by Nippon Zeon Co., Ltd. can be used.

The crosslinkable rubber composition of the present invention is obtained by blending the above hydrogenated nitrile group-containing rubber with an amine crosslinker.
According to the present invention, by combining a hydrogenated nitrile group-containing rubber with an amine-based cross-linking agent, the obtained cross-linked rubber can be effectively suppressed in deterioration of mechanical properties and volume change in acidic and alkaline environments. Therefore, it can be suitably used for applications that come into contact with acids or alkalis.

The amine-based cross-linking agent is not particularly limited as long as it is in the form of a compound having two or more amino groups, or a compound having two or more amino groups during cross-linking. A compound in which a plurality of hydrogen atoms of a group hydrocarbon is substituted with an amino group or a hydrazide structure (a structure represented by —CONHNH ₂ , CO represents a carbonyl group), and a compound in the form of that compound during crosslinking are preferred. .

Specific examples of amine-based cross-linking agents include aliphatic polyhydric compounds such as hexamethylenediamine, hexamethylenediamine carbamate, N,N-dicinnamylidene-1,6-hexanediamine, tetramethylenepentamine, and hexamethylenediamine cinnamaldehyde adducts. Amines; 4,4-methylenedianiline, m-phenylenediamine, 4,4-diaminodiphenyl ether, 3,4-diaminodiphenyl ether, 4,4-(m-phenylenediisopropylidene)dianiline, 4,4-(p -phenylenediisopropylidene)dianiline, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 4,4-diaminobenzanilide, 4,4-bis(4-aminophenoxy)biphenyl, m-xyl Aromatic polyvalent amines such as diamine, p-xylylenediamine and 1,3,5-benzenetriamine; , oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutamic acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, suberic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide, brassylic acid dihydrazide, dodecanedioic acid dihydrazide, acetone dicarboxylic acid dihydrazide, polyvalent hydrazides such as fumaric acid dihydrazide, maleic acid dihydrazide, itaconic acid dihydrazide, trimellitic acid dihydrazide, 1,3,5-benzenetricarboxylic acid dihydrazide, aconitic acid dihydrazide, and pyromellitic acid dihydrazide; Among these, aliphatic polyamines and aromatic polyamines are preferred, and hexamethylenediamine carbamate and 2,2-bis[ 4-(4-aminophenoxy)phenyl]propane is more preferred.

The content of the amine-based cross-linking agent in the cross-linkable rubber composition of the present invention is not particularly limited, but is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the hydrogenated nitrile group-containing rubber. It is preferably 0.2 to 15 parts by weight, more preferably 0.5 to 10 parts by weight. By setting the content of the amine-based cross-linking agent within the above range, the resulting cross-linked rubber can have better mechanical properties.

Moreover, the crosslinkable rubber composition of the present invention preferably further contains a basic crosslink accelerator.

Specific examples of basic cross-linking accelerators include 1,8-diazabicyclo[5,4,0]undecene-7 (hereinafter sometimes abbreviated as “DBU”), 1,5-diazabicyclo[4,3,0] nonene-5 (hereinafter sometimes abbreviated as "DBN"), 1-methylimidazole, 1-ethylimidazole, 1-phenylimidazole, 1-benzylimidazole, 1,2-dimethylimidazole, 1-ethyl-2-methylimidazole , 1-methoxyethylimidazole, 1-phenyl-2-methylimidazole, 1-benzyl-2-methylimidazole, 1-methyl-2-phenylimidazole, 1-methyl-2-benzylimidazole, 1,4-dimethylimidazole, 1,5-dimethylimidazole, 1,2,4-trimethylimidazole, 1,4-dimethyl-2-ethylimidazole, 1-methyl-2-methoxyimidazole, 1-methyl-2-ethoxyimidazole, 1-methyl-4 -methoxyimidazole, 1-methyl-2-methoxyimidazole, 1-ethoxymethyl-2-methylimidazole, 1-methyl-4-nitroimidazole, 1,2-dimethyl-5-nitroimidazole, 1,2-dimethyl-5 -aminoimidazole, 1-methyl-4-(2-aminoethyl)imidazole, 1-methylbenzimidazole, 1-methyl-2-benzylbenzimidazole, 1-methyl-5-nitrobenzimidazole, 1-methylimidazoline, 1 ,2-dimethylimidazoline, 1,2,4-trimethylimidazoline, 1,4-dimethyl-2-ethylimidazoline, 1-methyl-phenylimidazoline, 1-methyl-2-benzylimidazoline, 1-methyl-2-ethoxyimidazoline , 1-methyl-2-heptylimidazoline, 1-methyl-2-undecylimidazoline, 1-methyl-2-heptadecylimidazoline, 1-methyl-2-ethoxymethylimidazoline, 1-ethoxymethyl-2-methylimidazoline, etc. guanidine-based basic cross-linking accelerators such as tetramethylguanidine, tetraethylguanidine, diphenylguanidine, 1,3-di-ortho-tolylguanidine and orthotolylbiguanide; n-butyraldehyde Aldehydeamine-based basic cross-linking accelerators such as aniline and acetaldehyde ammonia; dicyclopentylamine, dicyclohexylamine, dicycloheptylamine dicycloalkylamines such as n; N-methylcyclopentylamine, N-butylcyclopentylamine, N-heptylcyclopentylamine, N-octylcyclopentylamine, N-ethylcyclohexylamine, N-butylcyclohexylamine, N-heptylcyclohexylamine, N-octylcyclooctylamine, N-hydroxymethylcyclopentylamine, N-hydroxybutylcyclohexylamine, N-methoxyethylcyclopentylamine, N-ethoxybutylcyclohexylamine, N-methoxycarbonylbutylcyclopentylamine, N-methoxycarbonylheptylcyclohexylamine , N-aminopropylcyclopentylamine, N-aminoheptylcyclohexylamine, di(2-chlorocyclopentyl)amine, di(3-chlorocyclopentyl)amine and other secondary amine-based basic cross-linking accelerators; Among these, guanidine-based basic cross-linking accelerators, secondary amine-based basic cross-linking accelerators and basic cross-linking accelerators having a cyclic amidine structure are preferred, and basic cross-linking accelerators having a cyclic amidine structure are more preferred. 1,8-diazabicyclo[5,4,0]undecene-7 and 1,5-diazabicyclo[4,3,0]nonene-5 are more preferred, and 1,8-diazabicyclo[5,4,0]undecene-7 is particularly preferred. The basic cross-linking accelerator having a cyclic amidine structure may form a salt with an organic carboxylic acid, an alkylphosphoric acid, or the like. In addition, the secondary amine-based basic cross-linking accelerator may be a mixture of alcohols such as alkylene glycol and alkyl alcohol having 5 to 20 carbon atoms, and further contains an inorganic acid and / or an organic acid. You can stay. The secondary amine-based basic cross-linking accelerator and the inorganic acid and/or the organic acid may form a salt and form a complex with the alkylene glycol.

The content of the basic cross-linking accelerator in the crosslinkable rubber composition of the present invention is not particularly limited, but is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the hydrogenated nitrile group-containing rubber, More preferably 0.2 to 15 parts by weight, still more preferably 0.5 to 10 parts by weight.

In addition, the crosslinkable rubber composition of the present invention preferably contains a filler from the viewpoint that the mechanical properties of the obtained crosslinked rubber can be further enhanced. The filler is not particularly limited as long as it is a filler commonly used in the rubber field, and both organic fillers and inorganic fillers can be used. , inorganic fillers are preferred.

As the inorganic filler, those commonly used for compounding rubber may be used, and examples thereof include carbon black, silica, clay, alumina, aluminum hydroxide, magnesium oxide, magnesium hydroxide, calcium oxide, and calcium hydroxide. , aluminum magnesium oxide, titanium oxide, kaolin, pyrophyllite, bentonite, talc, attapulgite, magnesium calcium silicate, aluminum silicate, magnesium silicate, calcium silicate, crystalline aluminosilicate, and the like. Among these, carbon black, silica and clay are preferably used. An inorganic filler can be used individually by 1 type or in combination of multiple types.

As the carbon black, any one commonly used for rubber compounding can be used, and examples thereof include furnace black, acetylene black, thermal black, channel black, and graphite.

Examples of silica include, but are not limited to, natural silica such as quartz powder and silica powder; synthetic silica such as silicic anhydride (silica gel, aerosil, etc.) and hydrated silicic acid; among these, synthetic silica is preferred.

The clay is not particularly limited as long as it is a natural mineral containing hydrous aluminum silicate as a main component, and examples thereof include montmorillonite, pyrophyllite, kaolinite, halloysite and sericite.

Examples of inorganic fillers include coupling treatment with silane coupling agents, aluminum coupling agents, titanium coupling agents, etc., and higher fatty acid derivatives such as higher fatty acids or their metal salts, esters or amides, surfactants, etc. A material subjected to a surface modification treatment may also be used. At this time, the inorganic filler may be subjected to a surface modification treatment in advance, or a surface modifier such as a coupling treatment may be used together with the inorganic filler when preparing the rubber composition. may be used to perform surface modification treatment of the inorganic filler.

Silane coupling agents include, but are not limited to, γ-mercaptopropyltrimethoxysilane, mercaptomethyltrimethoxysilane, mercaptomethyltriethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, bis(3-tri Sulfur-containing silane coupling agents such as ethoxysilylpropyl)disulfane; γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane , γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, epoxy group-containing silane coupling agents; N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropyl trimethoxysilane, γ-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-triethoxy Amino group-containing silane coupling agents such as silyl-N-(1,3-dimethyl-butylidene)propylamine and N-phenyl-3-aminopropyltrimethoxysilane; γ-methacryloxypropyltrimethoxysilane, γ-methacryloxy (Methoxysilane) such as propyltris(β-methoxyethoxy)silane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, etc. ) acryloxy group-containing silane coupling agents; vinyl group-containing silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, vinyltrichlorosilane, vinyltriacetoxysilane; 3-chloropropyl chloropropyl group-containing silane coupling agents such as trimethoxysilane; isocyanate group-containing silane coupling agents such as 3-isocyanatopropyltriethoxysilane; styryl group-containing silane coupling agents such as p-styryltrimethoxysilane; ureido group-containing silane coupling agents such as ethoxysilane; allyl group-containing silane coupling agents such as diallyldimethylsilane; alkoxy group-containing silane coupling agents such as tetraethoxysilane; phenyl group-containing silane coupling agents such as diphenyldimethoxysilane; fluoro group-containing silane coupling agents such as trifluoropropyltrimethoxysilane; alkyl group-containing silane coupling agents such as isobutyltrimethoxysilane and cyclohexylmethyldimethoxysilane; mentioned.
Aluminum-based coupling agents include acetoalkoxyaluminum diisopropylate, aluminum diisopropoxymonoethylacetoacetate, aluminum trisethylacetoacetate, and aluminum trisacetylacetonate.
Titanate-based coupling agents include isopropyl triisostearoyl titanate, isopropyl tris(dioctylpyrophosphate) titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, tetraoctylbis(ditridecylphosphite) titanate, tetra(2 , 2-diallyloxymethyl-1-butyl)bis(ditridenyl)phosphite titanate, bis(dioctylpyrophosphate)oxyacetate titanate, bis(dioctylpyrophosphate)ethylene titanate, tetraisopropylbis(dioctylphosphite)titanate, isopropyl tri isostearoyl titanate and the like.
These can be used singly or in combination.

The content of the inorganic filler in the crosslinkable rubber composition of the present invention is not particularly limited, but is preferably 1 to 200 parts by weight, more preferably 5 parts by weight, based on 100 parts by weight of the hydrogenated nitrile group-containing rubber. 150 parts by weight, more preferably 10 to 100 parts by weight, particularly preferably 20 to 80 parts by weight. By setting the content of the inorganic filler within the above range, the resulting crosslinked rubber can be made more excellent in resistance to hardening in oil under a heating environment.

In addition to the above, the crosslinkable rubber composition of the present invention may contain compounding agents commonly used in the rubber field, such as metal oxides such as zinc oxide and magnesium oxide, and alpha compounds such as zinc methacrylate and zinc acrylate. , β-ethylenically unsaturated carboxylic acid metal salts, plasticizers, co-crosslinking agents, cross-linking aids, cross-linking retarders, anti-aging agents, antioxidants, light stabilizers, anti-scorch agents such as primary amines, diethylene glycol, etc. Activators, processing aids, lubricants, adhesives, lubricants, flame retardants, antifungal agents, acid acceptors, antistatic agents, pigments, foaming agents and the like can be blended. The blending amount of these compounding agents is not particularly limited as long as it does not impair the object and effect of the present invention, and the amount can be blended according to the blending purpose.

Furthermore, the crosslinkable rubber composition of the present invention may be compounded with a rubber other than the hydrogenated nitrile group-containing rubber described above as long as the effects of the present invention are not hindered. Rubbers other than hydrogenated nitrile group-containing rubbers include acrylic rubber, ethylene-acrylic acid copolymer rubber, fluororubber, styrene-butadiene copolymer rubber, polybutadiene rubber, ethylene-propylene copolymer rubber, ethylene-propylene- Diene terpolymer rubbers, epichlorohydrin rubbers, urethane rubbers, chloroprene rubbers, silicone rubbers, fluorosilicone rubbers, chlorosulfonated polyethylene rubbers, natural rubbers and polyisoprene rubbers can be mentioned. When a rubber other than the hydrogenated nitrile group-containing rubber is blended, the amount is preferably 30 parts by weight or less, more preferably 20 parts by weight or less, and 10 parts by weight or less per 100 parts by weight of the hydrogenated nitrile group-containing rubber. is particularly preferred.

The crosslinkable rubber composition of the present invention is prepared by mixing the above components preferably in a non-aqueous system. Although the method for preparing the crosslinkable rubber composition of the present invention is not limited, usually, the components excluding the crosslinker and heat-labile components (for example, crosslink aids) are mixed in a Banbury mixer, an intermixer, a kneader, and the like. After primary kneading with a mixer such as a mixer, the mixture is transferred to a roll or the like, a cross-linking agent, a heat-labile component, and the like are added, followed by secondary kneading.

<Rubber cross-linked product>
The rubber cross-linked product of the present invention is obtained by cross-linking the above-described cross-linkable rubber composition of the present invention.
The cross-linked rubber product of the present invention is obtained by molding the cross-linkable rubber composition of the present invention into a desired shape using a molding machine such as an extruder, an injection molding machine, a compressor, or a roll, and then heating. It can be manufactured by performing a cross-linking reaction with and fixing the shape as a cross-linked product. In this case, the cross-linking may be performed after pre-molding, or the cross-linking may be performed at the same time as the molding. The molding temperature is usually 10-200°C, preferably 25-120°C. The crosslinking temperature is usually 100 to 200°C, preferably 130 to 190°C, and the crosslinking time is usually 1 minute to 24 hours, preferably 2 minutes to 1 hour.

Further, depending on the shape, size, etc. of the crosslinked product, even if the surface is crosslinked, the interior may not be sufficiently crosslinked, so secondary crosslinking may be performed by further heating.
As a heating method, a general method used for cross-linking rubber such as press heating, steam heating, oven heating, and hot air heating may be appropriately selected.

Since the rubber crosslinked product of the present invention thus obtained is obtained using the above-described crosslinkable rubber composition of the present invention, there is no decrease in mechanical properties and volume change in acidic and alkaline environments. It is effectively suppressed, so it can be suitably used for applications that come into contact with acids or alkalis, particularly applications that come into contact with gases containing acids or alkalis, such as blow-by gas or EGR gas. It can be suitably used for applications that come into contact with. Specifically, the cross-linked rubber product of the present invention can be suitably used as blow-by gas hoses, EGR hoses, and gaskets, seals, etc. connected to these hoses.

In addition to the above, the cross-linked rubber product of the present invention can also be used for O-rings, packings, diaphragms, oil seals, shaft seals, bearing seals, well head seals, shock absorber seals, pneumatic equipment seals, and cooling of air conditioners. Freon or fluorohydrocarbon or carbon dioxide sealing seals used in equipment and air conditioner refrigerator compressors, supercritical carbon dioxide or subcritical carbon dioxide sealing seals used as cleaning media for precision cleaning, transfer Various sealing materials such as seals, valves, valve seats, BOP (Blow Out Preventer), platters, etc. for dynamic devices (rolling bearings, automotive hub units, automotive water pumps, linear guide devices, ball screws, etc.); Intake manifold gasket attached to the connecting part with the cylinder head, cylinder head gasket attached to the connecting part between the cylinder block and the cylinder head, rocker cover gasket attached to the connecting part between the rocker cover and the cylinder head, oil pan and cylinder block or transmission case, gasket for fuel cell separator installed between a pair of housings sandwiching a unit cell with positive electrode, electrolyte plate and negative electrode, top cover of hard disk drive various gaskets such as gaskets; various rolls such as printing rolls, iron manufacturing rolls, paper manufacturing rolls, industrial rolls, business machine rolls; flat belts (film core flat belts, cord flat belts, laminated flat belts, single unit type flat belts, etc.), V-belts (wrapped V-belts, raw edge V-belts, etc.), V-ribbed belts (single V-ribbed belts, double V-ribbed belts, wrapped V-ribbed belts, back rubber V-ribbed belts, upper cog V-ribbed belts, etc.), CVT belts, Various belts such as timing belts, toothed belts, conveyor belts; fuel hoses, turbo air hoses, oil hoses, radiator hoses, heater hoses, water hoses, vacuum brake hoses, control hoses, air conditioner hoses, brake hoses, power steering hoses , air hoses, marine hoses, risers, flow lines, and other hoses; CVJ boots, propeller shaft boots, constant velocity joint boots, rack and pinion boots, and other boots; Attenuation rubber parts such as dynamic dampers, rubber couplings, air springs, anti-vibration materials, clutch facing materials; dust covers, automobile interior parts, friction materials, tires, coated cables, shoe soles, electromagnetic wave shields, adhesion for flexible printed circuit boards It can be used for a wide range of applications such as adhesives such as agents, fuel cell separators, and the electronics field.

EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In the following, "parts" are by weight unless otherwise specified. Physical properties and properties are tested or evaluated as follows.

<Normal physical properties (tensile strength, elongation)>
The crosslinkable rubber composition was placed in a mold of 15 cm long, 15 cm wide and 0.2 cm deep, and press-molded at 170° C. for 20 minutes at a press pressure of 10 MPa to obtain a cross-linked rubber sheet. Next, the resulting crosslinked rubber product was transferred to a gear oven and subjected to secondary crosslinking at 170° C. for 4 hours. Using the obtained test piece, the tensile strength and elongation at break of the crosslinked rubber product were measured according to JIS K6251:2017.

<Acid aqueous solution immersion test>
A sheet-like crosslinked rubber product obtained in the same manner as in the evaluation of the normal physical properties was subjected to an acidic aqueous solution immersion test. Specifically, a sheet-like crosslinked rubber product is immersed in an acidic aqueous solution (a mixed aqueous solution of 600 ppm by weight of sulfuric acid, 600 ppm by weight of nitric acid, and 1800 ppm by weight of acetic acid) in an autoclave at 150° C. for 1008 hours. The crosslinked rubber was taken out from the acidic aqueous solution to obtain a crosslinked rubber after the acidic aqueous solution immersion test. Then, the tensile strength and elongation at break of the cross-linked rubber after the acidic aqueous solution immersion test were measured in the same manner as the evaluation of the normal physical properties described above, and the tensile strength in the normal state before the acidic aqueous solution immersion test. , and the rate of change with respect to the elongation at break was calculated.
In addition, the volume of the crosslinked rubber product before the acidic aqueous solution immersion test and the volume of the rubber crosslinked product after the acidic aqueous solution immersion test were measured, respectively, and the volume change rate before and after the acidic aqueous solution immersion test was measured according to the following formula. The volume change rate was measured not only for the cross-linked rubber that had been heated for 1008 hours in the acidic aqueous solution immersion test, but also for the cross-linked rubber that had been heated for 504 hours in the acidic aqueous solution immersion test.
Volume change rate before and after the acidic aqueous solution immersion test (%) = (volume of the cross-linked rubber product after the acidic aqueous solution immersion test - volume of the cross-linked rubber product before the acidic aqueous solution immersion test) ÷ volume of the cross-linked rubber product before the acidic aqueous solution immersion test ×100

<Ammonia aqueous solution immersion test>
Ammonia aqueous solution immersion test was performed on the sheet-like crosslinked rubber product obtained in the same manner as in the evaluation of the physical properties in the normal state. Specifically, a sheet-like crosslinked rubber product is immersed in an aqueous ammonia solution (an aqueous solution of 3000 ppm by weight of ammonia) at 150°C for 1008 hours in an autoclave, and then the crosslinked rubber product is taken out of the aqueous ammonia solution and treated with ammonia. A rubber cross-linked product was obtained after the aqueous solution immersion test. Then, the tensile strength and the elongation at break of the crosslinked rubber after the ammonia aqueous solution immersion test were measured in the same manner as the evaluation of the normal physical properties described above, and the normal tensile strength before the ammonia aqueous solution immersion test. , and the rate of change with respect to the elongation at break was calculated.
In addition, the volume of the crosslinked rubber product before the ammonia aqueous solution immersion test and the volume of the rubber crosslinked product after the ammonia aqueous solution immersion test were measured, respectively, and the volume change rate before and after the ammonia aqueous solution immersion test was measured according to the following formula. The volume change rate was measured not only for the rubber crosslinked product heated for 1008 hours in the ammonia aqueous solution immersion test, but also for the rubber crosslinked product heated for 504 hours in the ammonia aqueous solution immersion test.
Volume change rate before and after the ammonia aqueous solution immersion test (%) = (volume of the crosslinked rubber after the ammonia aqueous solution immersion test - volume of the crosslinked rubber before the ammonia aqueous solution immersion test) / volume of the rubber crosslinked before the ammonia aqueous solution immersion test ×100

<Example 1>
Hydrogenated nitrile group-containing rubber (trade name “Zetpol 2510”, manufactured by Nippon Zeon Co., Ltd., acrylonitrile unit content: 35.2% by weight, iodine value 12 or less, Mooney viscosity (ML1+4, 100 ° C.) 45) 100 parts, carbon Black (trade name "Seist SO", manufactured by Tokai Carbon Co., Ltd., inorganic filler) 40 parts, tri-2-ethylhexyl trimellitate (trade name "ADEKA CIZER C-8", manufactured by ADEKA, plasticizer) 5 parts, 1 part of stearic acid, 1 part of polyoxyethylene alkyl ether phosphate (trade name "Phosphanol RL210", manufactured by Toho Chemical Industry Co., Ltd.), and 4,4'-di-(α,α-dimethylbenzyl) diphenylamine ( 1.5 parts of anti-aging agent (trade name: "Nocrac CD", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) was mixed in a kneader at 50°C for 5 minutes. The resulting mixture was then transferred to a roll at 50° C. and 2.4 parts of hexamethylene diamine carbamate (trade name “Diak #1”, manufactured by DuPont, amine-based cross-linking agent) and 1,8-diazabicyclo [5 ,4,0]-undecene-7 (DBU) (trade name “RHENOGRAN XLA-60 (GE2014), manufactured by Rhein Chemie, DBU 60% (including a portion that is a zinc dialkyl diphosphate salt), promoting basic cross-linking Agent) were blended and kneaded to obtain a crosslinkable rubber composition.

Then, using the obtained crosslinkable rubber composition, measurement of physical properties (tensile strength, elongation) in the normal state, and an acidic aqueous solution immersion test and an ammonia aqueous solution immersion test were performed according to the above methods. Table 1 shows the results.

<Comparative Example 1>
Hydrogenated nitrile group-containing rubber (trade name “Zetpol 2010”, manufactured by Nippon Zeon Co., Ltd., acrylonitrile unit content: 36.2% by weight, iodine value 11 or less, Mooney viscosity (ML1+4, 100 ° C.) 85) 100 parts, carbon Black (trade name "Seist SO", manufactured by Tokai Carbon Co., Ltd., inorganic filler) 40 parts, tri-2-ethylhexyl trimellitate (trade name "ADEKA CIZER C-8", manufactured by ADEKA, plasticizer) 5 parts, 1 part of stearic acid, 4,4'-di-(α,α-dimethylbenzyl)diphenylamine (trade name "Nocrac CD", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., anti-aging agent) 1.5 parts, and 2-mercapto 1.5 parts of benzimidazole (trade name “Nocrac MB”, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., anti-aging agent) was blended and mixed in a kneader at 50° C. for 5 minutes. Next, the resulting mixture was transferred to a roll at 50° C., and 1,3-bis(t-butylperoxyisopropyl)benzene (trade name “Vulcup40KE”, manufactured by Hercules, organic peroxide cross-linking agent, 40% product). A crosslinkable rubber composition was obtained by blending and kneading 8 parts.

Then, using the obtained crosslinkable rubber composition, measurement of physical properties (tensile strength, elongation) in the normal state, and an acidic aqueous solution immersion test and an ammonia aqueous solution immersion test were performed according to the above methods. Table 1 shows the results.

<Evaluation of Example 1 and Comparative Example 1>
From Table 1, according to the crosslinkable rubber composition containing the hydrogenated nitrile group-containing rubber and the amine-based crosslinker, the crosslinked rubber obtained has mechanical properties (tensile strength, elongation) and volume change were effectively suppressed (Example 1).
On the other hand, when an organic peroxide cross-linking agent is used instead of the amine-based cross-linking agent, the resulting cross-linked rubber exhibits a decrease in mechanical properties (tensile strength, elongation) and volume reduction in acidic and alkaline environments. The result was that both changes were large (Comparative Example 1).

<Examples 2 to 230>
Crosslinkable rubber compositions were obtained with the formulations shown in Tables 2 to 20, and sheet-like crosslinked rubber products were obtained in the same manner as in the evaluation of normal physical properties.
In Examples 2 to 230, the hydrogenated nitrile group-containing rubber shown in each table and the compounding agent were blended in the amounts shown in each table, mixed at 50°C for 5 minutes, and then the resulting mixture. was transferred to a roll at 50° C., and the cross-linking agent and cross-linking accelerator shown in each table were blended and kneaded to obtain a cross-linkable rubber composition.
Since the crosslinkable rubber compositions according to Examples 2 to 230 also contain a hydrogenated nitrile group-containing rubber and an amine-based crosslinker, the resulting crosslinked rubbers are, as in Example 1, acid Alternatively, it is considered that it can be suitably used for applications that come into contact with alkali.

The rubbers and compounding agents shown in each table are as follows.
Zetpol 1510: Hydrogenated nitrile group-containing rubber (trade name “Zetpol 1510”, manufactured by Zeon Corporation, acrylonitrile unit content: 43.5% by weight, iodine value 12 or less, Mooney viscosity (ML1+4, 100°C) 41)
・ Zetpol 2510: Hydrogenated nitrile group-containing rubber (trade name “Zetpol 2510”, manufactured by Zeon Corporation, acrylonitrile unit content: 35.2% by weight, iodine value 12 or less, Mooney viscosity (ML1+4, 100 ° C.) 45)
Zetpol 3710: Hydrogenated nitrile group-containing rubber (trade name “Zetpol 3710”, manufactured by Zeon Corporation, acrylonitrile unit content: 23.6% by weight, iodine value 12 or less, Mooney viscosity (ML1+4, 100°C) 48)
Zetpol 3610: Hydrogenated nitrile group-containing rubber (trade name “Zetpol 3610”, manufactured by Zeon Corporation, acrylonitrile unit content: 20.5% by weight, iodine value 12 or less, Mooney viscosity (ML1+4, 100 ° C.) 47.5 )
・ Zetpol 4610: Hydrogenated nitrile group-containing rubber (trade name “Zetpol 4610”, manufactured by Zeon Corporation, acrylonitrile unit content: 15.5% by weight, iodine value 12 or less, Mooney viscosity (ML1+4, 100 ° C.) 50)
・ SEAST SO: Carbon black (trade name “SEAST SO”, manufactured by Tokai Carbon Co., Ltd., inorganic filler)
・Nipsil ER: Silica (trade name “Nipsil ER”, manufactured by Tosoh Silica Corporation, BET specific surface area: 111 m ² /g)
Burgess KE: Surface-treated clay (trade name “Burgess KE”, manufactured by Burgess Pigment, aluminum silicate treated with a silane coupling agent, volume average particle size: 1.5 μm)
・ Adekasizer C-8: Tri-2-ethylhexyl trimellitate (trade name “Adekasizer C-8”, manufactured by ADEKA, plasticizer)
・Adekasizer RS-107: di(butoxyethoxyethyl) adipate (trade name “Adekasizer RS-107”, manufactured by ADEKA, plasticizer)
・ Phosphanol RL210: Polyoxyethylene alkyl ether phosphate (trade name “Phosphanol RL210”, manufactured by Toho Chemical Industry Co., Ltd.)
・ Structol HT750: Processing aid (trade name “Structol HT-750”, manufactured by Sil+Seilach Structol)
・ Nocrac CD: 4,4′-di-(α,α-dimethylbenzyl)diphenylamine (trade name “Nocrac CD”, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., anti-aging agent)
・Diak #1: hexamethylene diamine carbamate (trade name “Diak #1”, manufactured by DuPont, amine-based cross-linking agent)
・BAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]propane (trade name “BAPP”, manufactured by Wakayama Seika Kogyo Co., Ltd., amine-based cross-linking agent)
・XLA-60: 1,8-diazabicyclo[5,4,0]-undecene-7 (DBU) (trade name “RHENOGRAN XLA-60 (GE2014), manufactured by Rhein Chemie, DBU 60% (zinc dialkyl diphosphate salt including the part where it is), basic cross-linking accelerator)

Claims (4)

A crosslinkable rubber composition containing a hydrogenated nitrile group-containing rubber and an amine-based crosslinking agent, and used for applications in contact with acid or alkali. The crosslinkable rubber composition according to claim 1, which is used for applications in contact with blow-by gas or EGR gas. A rubber cross-linked product obtained by cross-linking the cross-linkable rubber composition according to claim 1 and used for applications in contact with acid or alkali. 4. The cross-linked rubber product according to claim 3, which is used for applications in contact with blow-by gas or EGR gas.