| 摘要 |
In a damper having a structure comprising a vibration body, a mass member and an elastic body through which the mass member is joined to the vibration body, the elastic body is formed from a cross-linking product of an EPDM composition, which comprises (a) 100 parts by weight of at least one kind of EPDM, whose propylene content in sum total of ethylene and propylene in the copolymerization rubber is 35-50 wt. %, or a blend rubber of at least one kind of EPDM and EPM, whose propylene content in sum total of ethylene and propylene in the blend rubber is 35-50 wt. %, the EPDM or the blend rubber having a Mooney viscosity (ML100) of not less than 40, (b) 5-50 parts by weight of alpha-olefin oligomer, which is a polymer of alpha-olefin represented by the general formula, CH<SUB>2</SUB>-CHR, where R is an alkyl group having 3-12 carbon atoms, with a number average molecular weight Mn of 300-1,400 and (c) 1-10 parts by weight of an organic peroxide cross-linking agent. The elastic body for use in the damper has a good balance between changes in spring constant at low temperatures and damping characteristics in the normal use temperature region.
|
