| abstract |
A rubber composition for tire sidewalls excellent in strength characteristics and resistance to fatigue from flexing and capable of giving fuel-saving tire sidewalls, which comprises (A) an unsaturated olefin copolymer prepared from (i) ethylene, (ii) an aromatic vinyl compound, (iii) a non-conjugated polyene and, if necessary, (iv) an α-olefin having 3 or more carbon atoms and having a (i) to (iv) molar ratio ranging from 100/0 to 40/60, a [(i) + (iv)] to (ii) molar ratio ranging from 98/2 to 60/40, an intrinsic viscosity [âν] of 1.0 to 6.0 dl/g as determined at 135 °C in decalin, and an iodine value of 10 to 50 and (B) a diene rubber. A rubber composition for tire treads capable of giving tire treads being excellent in strength characteristics, abrasion resistance and braking performance on the wet road surface (resistance to wet skid) and exhibiting low rolling resistance, which comprises (A') an unsaturated olefin copolymer prepared from (i) ethylene, (ii) an aromatic vinyl compound, (iii) a non-conjugated polyene and (iv) an α-olefin having 3 or more carbon atoms and having a (i) to (iv) molar ratio ranging from 100/0 to 40/60 and a [(i) + (iv)] to (ii) molar ratio ranging from 99/1 to 85/15, and (B) a diene rubber at a (A') to (B) weight ratio of 1/99 to 50/50. |