Rubber composition and pneumatic tire

摘要

A rubber composition comprising, expressed as parts by weight per 100 parts by weight of elastomer (phr), 10 to 40 phr of a polybutadiene rubber having a microstructure comprising 96 to 98 percent cis 1,4-isomeric units, 1 to 3 percent trans 1,4-isomeric units and 0.3 to 1 percent vinyl 1,2-content; 60 to 90 phr of a solution polymerized styrene-butadiene rubber functionalized with an alkoxysilane group and a primary amine group; 60 to 100 phr of silica having a CTAB specific surface area (S CTAB ) of between 40 and 525 m 2 /g and a BET specific surface area (S BET ) of between 45 and 550 m 2 /g; and no more than 5 phr of carbon black is disclosed. The rubber composition is preferably used in a tread of a pneumatic tire.