| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rubber composition capable of improving a fuel economical efficiency, breaking strength and processability in a balanced manner, and to provide a pneumatic tire using the same. <P>SOLUTION: The rubber composition includes silica, a silane coupling agent having a mercapto group, and a conjugated diene-based polymer obtained by reacting a nitrogen and/or silicon-containing compound with the active terminal of a copolymer obtained by polymerizing a monomer component including a conjugated diene compound and silicon-containing vinyl compound using a polymerization initiator represented by formula (I) (wherein i is 0 or 1; R<SP POS="POST">11</SP>is 1-100C hydrocarbylene; R<SP POS="POST">12</SP>and R<SP POS="POST">13</SP>are each hydrocarbyl which may have substituents or trihydrocarbylsilyl, or hydrocarbylene which may have as a hetero atom, at least one atom selected from the atom group consisting of silicon, nitrogen and oxygen, while R<SP POS="POST">12</SP>and R<SP POS="POST">13</SP>bond to each other; and M is an alkali metal atom). The content of the conjugated diene-based polymer is ≤90 mass% in 100 mass% of a rubber component. The content of silica is 5-40 pts.mass based on 100 pts.mass of the rubber component, and that of the silane coupling agent is 1-20 pts.mass based on 100 pts.mass of silica. <P>COPYRIGHT: (C)2013,JPO&INPIT |
