Improved tread compound wet/winter traction using brominated isobutylene-co-para-methylstyrene

Use of brominated isobutylene-co-para-methylstyrene (BIMS) improves the lab oratory dynamic properties predictive of wet and winter traction of formula tions modeling all-season, winter and high-traction passenger tire treads. Blends of BIMS with cis-polybutadiene, natural rubber, and solution-polymer ized styrene-butadiene rubbers having varying microstructures were studied in silica-filled compounds. Selective substitution of the BIMS elastomer wa s made in order to evaluate the impact on abrasion resistance, and temperat ure-dependent tangent delta values. Use of BIMS requires adjustments to the curative system. By reducing both sulfur and accelerator(s) levels, compou nd cure and mechanical properties can be maintained. The level of silane co upling agent can also be reduced when using the BIMS elastomer.