SELF-CURABLE ALKENYL-HYDROGENATED SILOXANE COPOLYMER AND PREPARATION OF COATING COMPOSITION

摘要

PROBLEM TO BE SOLVED: To achieve an excellent high-temp. resistance by forming a curable compsn. contg. a hydrogenated silicone copolymer and a hydrosilylation catalyst. SOLUTION: A cyclic organosiloxane (e.g. octamethylcyclotetrasiloxane) is thermally reacted in the presence of an alkali metal silanolate catalyst. The resultant hydrogenation product [e.g. HOSiR<1> R<2> (Dq )SiR<1> R<2> OH] is neutralized with a phosphorus nitride halide such as phosphorus nitride chloride represented by the formula: [X3 P(NPX2 )n PX3 ]PX4 <-> (wherein n is 1-6) and subjected to condensation with a hydrogen-contg. organosiloxane represented by the formula: MDHM (wherein M is R<4> R<5> R<6> SiO1/2 ; and DH is SiR<3> HO2/2 ) to give a hydrogenated silicone copolymer represented by the formula: Mu Dq Tr Qs (wherein Dq is SiR<1> R<2> O2/2 ; T is R<7> SiO3/2 ; Q is SiO4/2 ; and R<1> to R<7> are each H or a 1-40C hydrocarbon group). This copolymer is compounded with a hydrosilylation catalyst to give a curable compsn.