气相法二氧化硅对室温硫化硅橡胶性能的影响

摘要

The influence of the surface area,contents,drying reduction of fumed silica and the sequence of the adding materials on the properties of RTV silicone rubber was studied. Results showed that RTV com-prehensive performance would be better when using fumed silica with the specific surface area of 150 m2/g and dry reduction of 0.5% as the reinforcing filler,30 parts,and the sequence was that using 107 silicone rubber mixed with methyl silicone oil,then added methyl acetoxyl silane,silicon dioxide,and the dibutyltin dilaurate in order. The rubber had a good thixotropy,tack-free time of 6 min,the tensile strength of 0.94 MPa,the e-longation rate of 386%,and the smooth surface after Butterfly test.%研究了气相法二氧化硅的比表面积、用量、干燥减量和物料加入顺序对室温硫化 (RTV) 硅橡胶性能的影响.结果表明,采用比表面积150 m2/g和干燥减量0.5%的气相法二氧化硅为补强填料,用量为30份,且采用107硅橡胶与甲基硅油混合后再依次加入甲基三乙酰氧基硅烷、二氧化硅,最后加入催化剂二月桂酸二丁基锡的加料顺序时,制得的RTV硅橡胶综合性能较佳,其触变性好,表干时间为6 min,拉伸强度为0.94 MPa,拉断伸长率为386%,蝴蝶实验后胶料表面光滑.