| abstract |
Disclosed is an ethylene-propylene-diene terpolymer having isotactic polypropylene crystallinity compounded with a blend rubber wherein the terpolymer can be present in an amount effective to improve tack, aged tensile strength retention, fatigue resistance, ozone cracking resistance, and reversion resistance. Also disclosed is an elastomer composition wherein the terpolymer can have at least 60 wt % propylene-derived units, at least 6 wt % ethylene-derived units and from 0.3 to 10 wt % diene-derived units, and a tire sidewall composition comprising from 10 to 30 phr terpolymer, from 20 to 60 phr natural rubber, from 20 to 60 phr polybutadiene rubber, and an optional secondary blend rubber. Also disclosed is a vulcanizate of the elastomer composition, and articles, tire sidewalls, tires, retreaded tires, bias truck tires, off-road tires, and passenger automobile tires made with the vulcanizate. Further disclosed are processes for making molded articles and tires, and for retreading tires. |