Tire tread base containing syndiotactic-1,2-polybutadiene with diverse carbon blacks

摘要

A pneumatic rubber tire having a circumferential tread of a cap/base configuration comprising an outer tread cap rubber layer and an inner or internal tread rubber layer underlying the outer tread cap rubber layer is disclosed. The inner or internal tread rubber layer comprises a rubber composition comprising, based upon parts by weight per 100 parts by weight rubber (phr):(A) rubber(s) comprising:(1) 2 to 100 phr of syndiotactic-1,2-polybutadiene, and(2) from zero to 98 phr of at least one additional elastomer;(B) from 20 to 70 phr of rubber reinforcing carbon blacks comprising:(1) 10 to 40 phr of a first rubber reinforcing carbon black having an Iodine absorption value (ASTM D2515) in a range of from 6 to 50 g/kg and a dibutylthalate (DBP) absorption value (ASTM D2414) in a range of from 30 to 200 cc/100g,(2) 10 to 40 phr of a second rubber reinforcing carbon black having an Iodine absorption value (ASTM D2515) in a range of from 100 to 1000 g/kg (ASTM D2515) and a dibutylthalate (DBP) absorption value (ASTM D2414) in a range of from 95 to 135 cc/100g.