METHOD FOR PRODUCING POLYMETHYLPHENYLSILSESQUIOXANES Russian patent published in 2017 - IPC C08G77/06 

FIELD: chemistry.

SUBSTANCE: method is proposed for producing polymethylphenylsilsesquioxanes by homogeneous hydrolytic copolycondensation of mixtures of methyl- and phenyltrichlorosilanes at 0-80°C in aprotic organic solvents containing urea and acetone, during the interaction of which in the process, water for hydrolysis of chlorosilanes and a nitrogenous base for binding the hydrogen chloride evolved in this process are simultaneously generated. The molar ratio of trichlorosilane: carbamide: acetone is 1.0:(3.0-6.0):(3.0-12.0).

EFFECT: proposed method allows to produce highly functional branched, ladder and polycyclic polymethylphenylsilsesquioxanes, simplifies the isolation of the target products by eliminating the multiple washing of polymethylphenylsilsesquioxanes from acidic impurities, prevents the formation of gel-like products of hydrolytic polycondensation, and improves environmental safety and technical and economic parameters of the process.

3 cl, 1 tbl, 6 ex