Process for production of modified conjugated diene rubber, modified conjugated diene rubber, and rubber composition

Abstract

To provide a producing method of conjugated diene rubber which can be used as a starting material of cross-linked rubber which is used for such as tire tread and can enhance low fuel consumption performance. The method of producing modified conjugated diene rubber, comprising: a process step (a) wherein a conjugated diene polymer with an alkali metal or alkaline-earth metal active terminal, which polymer is obtained from polymerization of a conjugated diene compound or polymerization of a conjugated diene compound with an aromatic vinyl compound, is allowed to react with a hydrocarbyloxysilane compound having in its molecule at least one or more of each of the following functional groups (I): a hydrocarbyloxysilyl group and (II): a nitrogen-containing group formed by substituting one protective group for one hydrogen atom of a secondary amine, a tertiary amino group, an imino group, a pyridyl group to obtain a modified conjugated diene polymer with the functional group (II), and a process step (b) wherein the modified conjugated diene polymer produced in the process step (a) is mixed with an onium-forming agent.