To obtain a rubber composition reduced in fatigue crazing without detriment to adhesion to the adjoining component of a tire and hysteresis by using a rubber blend comprising a high-molecular-weight EPDM, an isoolefin/p- alkylstyrene copolymer and an additional diene elastomer.
This tire is a pneumatic rubber tire the outside rubber side wall of which is made from a sulfur-curing composition comprising about 5 to about 25phr (per 100 pts.wt. rubber, the same shall apply hereinbelow) of a high-molecular-weight EPDM being a rubbery terpolymer comprising ethylene, propylene and a small amount of a nonconjugated diene and having a molecular weight of about 500,000 to about 1,000,000, about 25 to about 50phr of a post- halogenated rubbery copolymer comprising an isoolefin (4-7C) and a p- alkylstyrene with a 1-11C alkyl and about 25 to about 75phr of at least one additional diene elastomer.
MASON ROGER ALLAN
EISENTROUT SONYA DENISE