Acrylic rubber composition and rubber crosslinked product
An acrylic rubber composition includes an acrylic rubber and a specific antioxidant, wherein the acrylic rubber includes 15 to 55% by weight of methacrylic acid alkyl ester monomer units (a), 44.5 to 84.5% by weight of acrylic acid ester monomer units (b), and 0.5 to 4% by weight of carboxyl group-containing monomer units (c), and the content of the antioxidant is 0.1 to 5 parts by weight relative to 100 parts by weight of the acrylic rubber.
1 . An acrylic rubber composition comprising an acrylic rubber and an antioxidant,
wherein the acrylic rubber comprises:
17.5 to 43% by weight of methacrylic acid alkyl ester monomer units (a);
55.5 to 81% by weight of acrylic acid ester monomer units (b); and
1 to 2% by weight of carboxyl group-containing monomer units (c),
the antioxidant is a compound represented by General Formula (9),
the methacrylic acid alkyl ester monomer units (a) are at least one selected from the group consisting of methyl methacrylate units, ethyl methacrylate units, n-butyl methacrylate units, and n-hexyl methacrylate units,
the acrylic acid ester monomer units (b) are at least one selected from the group consisting of ethyl acrylate units, and n-butyl acrylate units,
the carboxyl group-containing monomer units (c) are monoesters of C 4 to C 12 α,β-, and
the content of the antioxidant is 0.5 to 2.5 parts by weight relative to 100 parts by weight of the acrylic rubber:
where, in General Formula (9), R a and R b each independently represent an α-methylbenzyl group, an α,α-dimethylbenzyl group, a phenyl group, or a 4-methylphenyl group; and Z a and Z b each independently represent a chemical single bond.
2 . The acrylic rubber composition according to claim 1 , further comprising 0.05 to 20 parts by weight of a cross-linking agent relative to 100 parts by weight of the acrylic rubber.
3 . A cross-linked rubber prepared by cross-linking the acrylic rubber composition according to claim 2 .
4 . The cross-linked rubber according to claim 3 , wherein the cross-linked rubber is a hose material or a sealing material.
5 . The acrylic rubber composition according to claim 2 , wherein the cross-linking agent is an aromatic polyvalent amine compound.
6 . The acrylic rubber composition according to claim 1 , wherein the compound represented by General Formula (9) is a compound represented by General Formula (A):
7 . The acrylic rubber composition according to claim 1 , wherein the methacrylic acid alkyl ester monomer units (a) are at least one selected from the group consisting of methyl methacrylate units, ethyl methacrylate units, and n-butyl methacrylate units.