ゾル-ゲル法によりSBRラテックス中で合成したシリカの粒子径と補強効果に及ぼす反応条件の影響 Study on the Effect of Reaction Conditions for In Situ Silica Reinforcement of Styrene-Butadiene Rubber by Sol-gel Process in the Latex
Silica reinforcement of styrene-butadiene rubber(SBR) was carried out by sol-gel method using tetraethoxysilane(TEOS) in the SBR latex. Latex, TEOS, water and catalyst were mixed at room temperature, and the sol-gel reaction was conducted at 20, 40, 60°C. After conducting the sol-gel reaction, the system was held at 80°C for 8hrs under vacuum to remove water, alcohol and TEOS. The composite doped with the <i>in situ</i> silica was subjected to the vulcanization at 150°C. The effect of various reaction conditions (the amount of added TEOS, the amount of added catalyst, the molar ratio of TEOS and water in the mixture([H<sub>2</sub>O]/[TEOS]), the reaction temperature, the reaction time) on the particle size and reinforcing behavior of silica were discussed using the results of tensile test and SEM observation of the vulcanizates. Particle size of silica was greatly influenced by both the amount of added TEOS and [H<sub>2</sub>O]/[TEOS]. By controlling the conditions, finely dispersed silica particles, whose diameter was smaller than 100nm, were generated in the composites. Tensile modulus of composites was simply increased with increasing the silica content. Particle size of <i>in</i> <i>situ</i> silica did not so much influence the tensile modulus, but did the tensile strength at break.
日本ゴム協會誌 73(3), 144-151, 2000-03-15
THE SOCIRETY OF RUBBER SCIENCE AND TECHNOLOGYY, JAPAN