Patent ID: 7173087

Claim:
A hydrogenated nitrile rubber composition for producing a cross-linked product having a 20% modulus of 10 MPa or more, which comprises 100 parts by weight of hydrogenated nitrile rubber having a bound acrylonitrile content of 44.2â€“50% a median Mooney viscosity ML 1+4 (100Â° C.) of 75 or less and a median iodine value of 23 or less, and not less than 110 parts by weight in sum total as a filler comprising 30â€“100 parts by weight of carbon black and 10â€“80 parts by weight of graphite as a gas shielding filler, a volume fraction of the filler being 35â€“74% on the basis of the composition said hydrogenated nitrile rubber composition being substantially impermeable to pressurized carbon dioxide so as to function as a carbon dioxide sealant material.