| 摘要 |
PROBLEM TO BE SOLVED: To improve the performance of a ruber, e.g. low heat build-up properties, by improving the dispersibility of silica.SOLUTION: A method of producing a rubber composition includes a step of kneading 100 pts. mass of a diene rubber with 0.01-8 pts. mass of an azo compound of formula (1) to obtain a preliminary kneaded material and a step of kneading the preliminary kneaded material with 10-150 pts. mass of silica. In formula (1), R, R, Rand Rare a 1-3C alkyl group; R, R, Rand Rare hydrogen or a 1-3C alkyl group; Xand Xare a divalent group containing one or more of a thioether bond, an amide bond, a urethane bond, an ester bond, an ether bond, a thioester bond or a -CH(OH)-CH-NH- group; and n and m are an integer of 1-3. |
