| 摘要 |
PROBLEM TO BE SOLVED: To provide a rubber composition for a base tread capable of improving high mileage, fracture resistant strength and processability.SOLUTION: The rubber composition comprises a rubber component, silica (1) having a nitrogen adsorption specific surface area of 100 m/g or less, and silica (2) having a nitrogen adsorption specific surface area of 180 m/g or more. In 100 mass% of the rubber component, the following conjugate diene polymer is included by 5 mass% or more: the conjugate diene polymer is obtained by allowing an alkoxysilane compound to react with one end of a copolymer having monomer units based on a conjugate diene and based on compounds expressed by a formula (1) and a formula (2). The composition contains, with respect to 100 parts by mass of the rubber composition, 10 to 150 parts by mass of the silica (1) and silica (2) in total, satisfying an expression of: (content of silica (1))×0.2≤(content of silica (2))≤(content of silica (1))×6.5. In the formulae, Vrepresents a hydrocarbyl group having a polymerizable carbon-carbon double bond; Srepresents a substituted silyl group; and Arepresents a substituted amino group or a nitrogen-containing heterocyclic group. |
