摘要 |
A process for forming a silicone resin useful for making mica laminates comprising adding a mixture of organotrihalosilanes and dimethyldihalosilanes dissolved in a water immiscible organic solvent to a heterogeneous hydrolysis mixture composed of a water immiscible organic solvent and an alcohol and separating the solvent resin layer where the organic groups on said trihalosilane are methyl and phenyl with the mole percent concentration of the methyl groups to phenyl groups varying from 30 to 70 mole percent. The hydrolysis addition is generally carried out at a temperature of 25 DEG C to 80 DEG C. The resin produced by this process has an organo and methyl to Si ratio varying from 1.01 to 1 to 1.1 to 1. The alkoxy content is less than 6% by weight and, preferably, varies from 2 to 4% by weight and the silanol content is generally less than 6% by weight and preferably varies from 2 to 4% by weight.
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