Patent ID: 8580885

Claim:
A rubber composition characterized by compounding a polymer (B) comprising conjugated diene and having at least one functional group, an aromatic vinyl compound content of less than 5% by mass and a weight average molecular weight as measured without terminating by modification through a gel permeation chromatography and converted to polystyrene of not less than 2,000 but less than 150,000 and a filler (C) into a rubber component (A) having a weight average molecular weight as measured without terminating by modification through a gel permeation chromatography and converted to polystyrene of not less than 150,000, wherein the polymer (B) is produced by (1) (co)polymerizing monomers with a polymerization initiator to produce a (co)polymer having a polymerization active site and then modifying the polymerization active site with a modifying agent, or (2) (co)polymerizing monomers with a polymerization initiator having a functional group.