Treated silica for reinforcing silicone elastomer.

摘要

An improved reinforcing silica filler can be produced by treating a reinforcing silica, having a surface area of greater than 50 m<2>/g and from 0.5 to 6 parts by weight of adsorbed moisture per 100 parts by weight of silica, with a volatile treating agent comprising a combination of from 0.2 to 10 parts by weight of volatile treating agent of the formula VixSi(OR min )4-x and from 0.2 to 15 parts by weight of volatile treating agent of the formula PhxSi(OR min )4-x, where Vi is vinyl radical and Ph is phenyl radical. The improved reinforcing silica filler can be combined with polydiorganosiloxane and curing means to produce silicone elastomer compositions which can be cured to elastomers which have improved physical properties, such as compression set and heat aging.