Silicone ladder polymer and process for producing the same

摘要

A high-purity silicone ladder polymer of high molecular weight which contains 1 ppm or less of sodium, potassium, iron, copper, lead, magnesium, manganese and chlorine, and 1 ppb or less of uranium and thorium; and whose polymerization degree is 600 to 10000. Trialkoxysilane compounds or trichlorosilane compounds are hydrolyzed to produce a high-purity silicone ladder prepolymer whose polymerization degree is 5 to 600. The silicone ladder prepolymer is subjected to dehydrative condensation by using a nucleophilic reagent as a catalyst, and then purified in a dissolution/reprecipitation method to yield the silicone ladder polymer.