| 摘要 |
PROBLEM TO BE SOLVED: To provide a copolymer capable of providing a rubber composition and a pneumatic tire which are improved in fuel efficiency and wet grip performance in a balanced manner.SOLUTION: A copolymer is obtained by reacting a specific compound with an active terminal of a copolymer obtained by polymerizing a conjugate diene compound and a compound represented by formula (II) by use of a polymerization initiator represented by the following formula (1): RRN-(R)-M. The copolymer has a weight average molecular weight Mw of 1.0×10-2.5×10. |
