METHOD FOR PURIFYING SILICONE OIL

摘要

PURPOSE:To efficiently purify a silicone oil with reduced cost by extracting low molecular weight substances from a silicone oil containing methylphenylsiloxane. CONSTITUTION:A silicone oil is purified by bringing a phenylsilicone oil comprised of a copolymer comprised of methylphenylsiloxane units of the formula: -(-Si(CH3) (Ph)-O-)- (I) (wherein Ph represents a phenyl group) and dimethylsiloxane units of the formula: -(Si(CH3)2-O-)- (II) wherein the methylphenylsiloxane unit content of all the siloxane units is 50% or less into contact with carbon dioxide in a subcritical or supercritical state so as to extract off low molecular weight substances from the silicone oil.