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

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