Process for producing foamed rubber
AssigneeSumitomo Chemical Company, Limited
InventorJunichi Koshiba
Life of this patent
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Abstract
There are provided: (i) a process for producing a foamed rubber having a density of less than 0.50 g/cm3, which comprises the step of foaming and cross-linking a rubber composition containing (i) an ethylene-α-olefin copolymer rubber, (ii) a vulcanizing agent and (iii) a foaming agent having a particle diameter of not more than 10 μm in terms of a median diameter, wherein an amount of the foaming agent exceeds 4.0 parts by weight per 100 parts by weight of the ethylene-α-olefin copolymer rubber, and (ii) a sealing material for car use, which comprises the foamed rubber obtained by the above-mentioned process for producing a foamed rubber.
Claims15
A process for producing a foamed rubber having a density of from 0.30 to 0.50 g/cm3, which comprises the step of foaming and cross-linking a rubber composition containing (i) an ethylene-α-olefin-non-conjugated diene copolymer rubber satisfying the following conditions (A) to (D), (ii) a vulcanizing agent and (iii) a foaming agent;
- (A) a xylene-insoluble part in the copolymer rubber is from 5 to 20% by weight, or a cyclohexane-insoluble part therein is from 5 to 30% by weight,
- (B) a weight ratio of an ethylene polymerization unit/an α-olefin polymerization unit in the copolymer rubber is from 73/27 to 40/60,
- (C) a content of a non-conjugated diene polymerization unit in the copolymer rubber is from 18 to 36 in terms of an iodine value, and
- (D) Mooney viscosity (ML1+4(121° C.)) of the copolymer rubber measured according to JIS-K-6300-Mooney viscosity test is from 50 to 120.
A process for producing a foamed rubber having a density of less than 0.50 g/cm3, which comprises the step of foaming and cross-linking a rubber composition containing (i) an ethylene-α-olefin copolymer rubber, (ii) a vulcanizing agent and (iii) a foaming agent having a particle diameter of not more than 10 μm in terms of a median diameter, wherein an amount of the foaming agent exceeds 4.0 parts by weight per 100 parts by weight of the ethylene-α-olefin copolymer rubber.
Dependencies are inferred from the claim text.