Organopolysiloxane prepolymer and its cured form

Abstract

This invention provides organopolysiloxane prepolymers with excellent heat resistance and capable of providing a hardened body with adhesive properties. The organopolysiloxane prepolymers of embodiments of this invention are condensates of the following: (A) polydimethylsiloxanes having silyl groups at both ends; (B) at least one selected from the group consisting of alkoxy-containing silane oligomers, complete or partial hydrolysates of the silane oligomers, and condensates of the oligomers; (C) at least one selected from the group consisting of tetramethoxysilanes and tetraethoxysilanes; and (D) phenyl-containing silane compounds.