Abstract: A cross-linked rubber obtained by crosslinking a rubber composition containing a conjugated diene rubber and an inorganic filler, wherein when a loss tangent value of a non-interface component forming, of the cross-linked rubber ingredient, a portion other than an interface with the inorganic filler is represented as L(m) and a loss tangent value of an interface component forming, of the cross-linked rubber ingredient, an interface portion with the inorganic filler is represented as L(i), each loss tangent value being measured using an atomic force microscope in a state in which sinusoidal vibrations of 5 kHz are applied to the cross-linked rubber, the cross-linked rubber has a ratio L(i)/L(m) of 0.85 or less.

Abstract: A cross-linked rubber obtained by crosslinking a rubber composition containing a conjugated diene rubber and an inorganic filler, wherein when a loss tangent value of a non-interface component forming, of the cross-linked rubber ingredient, a portion other than an interface with the inorganic filler is represented as L(m) and a loss tangent value of an interface component forming, of the cross-linked rubber ingredient, an interface portion with the inorganic filler is represented as L(i), each loss tangent value being measured using an atomic force microscope in a state in which sinusoidal vibrations of 5 kHz are applied to the cross-linked rubber, the cross-linked rubber has a ratio L(i)/L(m) of 0.85 or less.

Abstract: A method of production of conjugated diene rubber including a first step of polymerizing a compound represented by a following formula (1) by using a polymerization initiator to obtain a polymer block of the compound represented by the formula (1) having an active end, and a second step of polymerizing a monomer containing at least a conjugated diene compound by using the active end of the polymer block, wherein, in the formula (1), R1 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R2 is a hydrocarbon group having 3 to 20 carbon atoms and containing a ring structure, each of R3 and R4 independently is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms which is substituted or unsubstituted, and X is arbitrary monovalent group.

Abstract: A method of production of conjugated diene rubber including a first step of polymerizing a compound represented by a following formula (1) by using a polymerization initiator to obtain a polymer block of the compound represented by the formula (1) having an active end, and a second step of polymerizing a monomer containing at least a conjugated diene compound by using the active end of the polymer block, wherein, in the formula (1), R1 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R2 is a hydrocarbon group having 3 to 20 carbon atoms and containing a ring structure, each of R3 and R4 independently is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms which is substituted or unsubstituted, and X is arbitrary monovalent group.