Abstract: The present invention addresses the problem of providing: a conjugated diene rubber composition which has excellent rebound resilience and wear resistance, while exhibiting good workability during rubber kneading and excellent wet grip performance; and a method for producing this conjugated diene rubber composition. The present invention provides a diene rubber composition which is obtained by subjecting a mixture of a diene rubber component 1 that is obtained by terminally modifying a conjugated diene polymer 1 with at least one silicon compound that is represented by formula (1) and/or formula (2) and a diene rubber component 2 that is obtained by terminally modifying a conjugated diene polymer 2 with at least one silicon compound that is represented by formula (1) and/or formula (2) to a hydrolysis process, and subsequently drying the resulting product.

Abstract: Studies have been made for the purpose of achieving both the improvement in the storage stability of a solution-polymerized diene rubber that is modified with an alkoxysilane compound and the improvement in the physical properties of the diene rubber when blended with silica. Thus, a production method whereby it becomes possible to produce a modified solution-polymerized diene rubber having good storage stability and high reactivity with silica is developed, by introducing several tens percent of a three blanched or four blanched component that has been coupled with a tin compound into a modified solution-polymerized diene rubber, then coagulating the resultant alkoxysilane modified diene rubber with steam and then drying the coagulated product.

Abstract: Provided are: a rubber composition (a silica master batch) that contains silica in a highly dispersed state, which is prepared by mixing a suspension with an emulsion of an emulsion-polymerized conjugated diene polymer and then coagulating the resultant mixture, wherein the suspension is prepared by highly dispersing wet silica, which does not undergo secondary coagulation yet, or silica, which is prepared by mechanically dissociating secondary coagulation masses of silica, in water and the emulsion-polymerized conjugated diene polymer contains a functional group that is reactive with silica or has high affinity for silica; and a method for producing the rubber composition. A clam (a small mass of a rubber) which contains silica in a highly dispersed state is hardly dried.