RUBBER COMPOSITION AND PNEUMATIC TIRE COMPRISING SAME

摘要

Disclosed is a rubber composition which enables the production of a tire having improved stable controllability on dry road surfaces and improved performance on ice.  More specifically, the rubber composition is characterized by comprising (A) a rubber component having a weight average molecular weight of greater than 150,000 in terms of polystyrene content, (B) an unmodified low-molecular-weight polymer which comprises a copolymer of an aromatic vinyl compound and a conjugated diene compound or a polymer of a conjugated diene compound and has a weight average molecular weight of greater than 80,000 and not greater than 150,000 in terms of polystyrene content, and (C) a filler, wherein the copolymer of an aromatic vinyl compound and a conjugated diene compound contains the aromatic vinyl compound attached therein in an amount of 5 mass% or less.  In the rubber composition, the low-molecular-weight polymer (B) is contained in an amount of 1 to 60 parts by mass relative to 100 parts by mass of the rubber component (A).