Process for preparing silicone rubber composition

摘要

The process comprises the steps of (A) mixing a base material (A-1), which is obtained by mixing an organopolysiloxane and a reinforcing silica and then heating the resulting mixture, with an aminosilane compound (A-2) represented by the formula:(R1)nSi[N(R2)2](4-n)wherein a plurality of R1 may be the same or different and are each a substituted or unsubstituted monovalent hydrocarbon group, a plurality of R2 may be the same or different and are each a substituted or unsubstituted monovalent hydrocarbon group, and n is 2 or 3; to allow them to react; and (B) heating the reaction mixture obtained in the step (A) under normal pressure or reduced pressure to remove an unreacted aminosilane compound and a by-product amine, contained in the reaction mixture. According to this process, a silicone rubber composition that can produce a silicone rubber cured product improved in compression set properties can be obtained without damaging other good properties inherent in silicone rubber.