| abstract |
A conjugated diene rubber of the present invention is prepared from conjugated diene polymer chains, wherein the conjugated diene polymer chains each has an active end at one end and an isoprene block at least at the other end, the isoprene block contains 70 wt % or more isoprene monomer units, and the active ends of at least part of the conjugated diene polymer chains are modified with a compound having a >C═O group as a functional group. This provides (i) a tire that has an excellent strength, excellent low-heat buildup property, and excellent wet grip property and (ii) a rubber composition and a conjugated diene rubber that are suitably used to produce the tire. |