| 摘要 |
The present invention relates to a branched conjugated diene copolymer which is useful for preparing a rubber composition, having high uniformity of a temperature dependence curve of a viscoelasticity tan´, for a tire, a rubber composition comprising the copolymer, and a pneumatic tire produced using the rubber composition for a tire. The branched conjugated diene copolymer is composed of monomer components comprising a branched conjugated diene compound represented by a general formula (1):
wherein R 1 represents an aliphatic hydrocarbon group having 6 to 11 carbon atoms, and an aromatic vinyl compound represented by a general formula (2):
wherein R 2 represents an aromatic hydrocarbon group having 6 to 10 carbon atoms, and R 5 represents a hydrogen atom or the like, and a copolymerization ratio (m) of the aromatic vinyl compound (2) is 45% by mass or more. |
