| 摘要 |
PROBLEM TO BE SOLVED: To produce a sealing tape excellent in adhesion to the surface of joint and tube made of polyethylene, resistance to gasoline, formability and executability, etc., useful for sealing of joints of gasoline transportation piping in a gasoline station by forming a specific rubber composition. SOLUTION: This rubber composition consist of (A) 25-60wt.%. of rubber comprising (A1 ) a nitrile rubber which is a solid at ambient temperature (e.g. a nitrile rubber consisting of butadiene unit and acrylonitrile unit in a ratio of 2:1-3:1 in mole and having the weight average molecular weight of 30×10<4> -50×40<4> , especially 40×10<4> -46×10<4> ) and (A2 ) a liquid nitrile rubber at ambient temperature (e.g. a depolymerization product of (A1 ) having the weight average molecular weight of 2500-3500, especially 2850-3150) in the weight ration of (A1 ):(A2 )=1:1.5-1:3 and (B) 40-75wt.%. of a filler such as talc, etc.
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