abstract |
A nitrile rubber composition comprising 5 to 50 parts by weight of carbon black, 5 to 60 parts by weight of graphite having an average particle diameter of 5 μm or less, 5 to 50 parts by weight of conductive carbon other than these carbon black and graphite, and 0.5 to 3.5 parts by weight of 2,5-di-tert-butylhydroquinone or 2,5-di-tert-amylhydroquinone as an antioxidant, based on 100 parts by weight of nitrile rubber. The nitrile rubber composition can yield a vulcanization molded product, besides maintaining characteristics as a conductive material, satisfying muddy water resistance, sealing properties, and low torque characteristics required for rolling bearing oil seals for vehicles, etc., and having a rubber volume change kept low when the product is washed with water after exposure to an antifreezing agent. |