| 摘要 |
PURPOSE:To provide a silicone rubber composition giving a cured product having improved elongation fatigue and flexural fatigue characteristics by mixing a specific diorganopolysiloxane, a reinforcing filler and an acidity-controlling agent, subjecting the mixture to a thermal treatment and subsequently mixing the product with a curing agent. CONSTITUTION:(A) diorganopolysiloxane having an average composition of the formula (R is 1-10C monovalent hydrocarbon, the plural R groups may be the same or different each other; (a) is 1.95-2.05) and having an average polymerization degree of 3000-30000, (B) 10-100 pts.wt. of a reinforcing filler (e.g. precipitated silica) in an amount of 10-100 pts.wt. based on 100 pts.wt. of the component A and (C) an acidity-controlling agent (preferably hydrochloric acid or sulfuric acid) in such an amount as the pH of an extracted solution prepared by extracting 50g of the 5wt.% toluene solution of the rubber composition with a 10g of deionized water is 3-5.5 are mixed each other. The mixture is subjected to a thermal treatment at 100-200 deg.C and further mixed with a curing agent to provide the objective rubber composition. |
