Abstract There is disclosed an organopolysilsesquioxane with the formula wherein R¹ is selected from the group consisting of substituted monovalent hydrocarbon groups and unsubstituted monovalent hydrocarbon groups; R², R³, and R⁴ are each selected from the group consisting of a hydrogen atom, unsubstituted monovalent hydrocarbon groups and substituted monovalent hydrocarbon groups, with the proviso that at least one R², R³ or R⁴ is selected from the group consisting of hydrogen and an aliphatically unsaturated hydrocarbon group; and n is a positive number, at least 80 weight percent of said organopolysilsesquioxane having a number-average molecular weight of 1,000 to 9,000.
Inventors
👤 Hisataka c/o Dow Corning T. S. Co. Ltd Nakashima
An organopolysilsesquioxane with the formula wherein R¹ is selected from the group consisting of substituted monovalent hydrocarbon groups and unsubstituted monovalent hydrocarbon groups; R², R³, and R⁴ are each selected from the group consisting of a hydrogen atom, unsubstituted monovalent hydrocarbon groups and substituted monovalent hydrocarbon groups, with the proviso that at least one R², R³ or R⁴ is selected from the group consisting of hydrogen and an aliphatically unsaturated hydrocarbon group; and n is a positive number, at least 80 weight percent of said organopolysilsesquioxane having a number-average molecular weight of 1,000 to 9,000.
Claim 2
Dependent Claim
186 words
An organopolysilsesquioxane prepared by a method comprising: (I) forming a two-layer system comprising (A) an aqueous layer which contains dissolved lower aliphatic alcohol and an alkali metal carboxylate and (B) an organic solvent layer which is not soluble in water in any proportion; (II) hydrolyzing and condensing an organotrihalosilane in said two-layer system, said organotrihalosilane having the formula R¹SiX₃ wherein R¹ is selected from the group consisting of substituted monovalent hydrocarbon groups and unsubstituted monovalent hydrocarbon groups and X is halogen; (III) reacting the product obtained in step (II) with a compound selected from the group consisting of a disilazane having the formula (R²R³R⁴Si)₂NH and a monohalosilane having the formula R²R³R⁴SiX, wherein X is halogen, R², R³, and R⁴ are each selected from the group consisting of a hydrogen atom, unsubstituted monovalent hydrocarbon groups and substituted monovalent hydrocarbon groups, with the proviso that at least one R², R³ or R⁴ is selected from the group consisting of hydrogen and an aliphatically unsaturated hydrocarbon group, with the further proviso that at least 80 weight percent of said organopolysilsesquioxane has a number-average molecular weight of 1,000 to 9,000.