| abstract |
A millable-type silicone rubber composition, a millable-type silicone rubber sponge, and a method for producing the sponge. (1): ???????? R 1 a SiO 4-a / 2 ????? (1) wherein R 1 is the same or different monovalent hydrocarbon groups, and a is 1.95 to 2.04 (B) reinforcing silica having at least two alkenyl groups in one molecule and having a degree of polymerization of 3,000 or more and having a degree of polymerization of 3,000 or more, (B) reinforcing silica (C) having a swelling initiation temperature of 90 to 150 DEG C and heating at 200 DEG C for 5 minutes (D) Curing agent: organic peroxide (E) Softening agent: A high-temperature decomposition type organic foaming agent having a decomposition initiation temperature of 180 DEG C or higher, wherein the curing of the component (A) Type silicone rubber sponge having a softening ratio of 20% or more by heat-treating the silicone rubber composition at 200 DEG C or higher. |