Intermediates of chemical assembling of oligoorganosiloxanes in hydrolysis of organochlorosilanes

The mechanism of the formation of oligoorganosiloxanes during the hydrolysis of organochlorosilanes was considered. A comparative estimation of a relationship of the degree of conversion of the monomer vs. degree of conversion of functional groups in the homo- and heterofunctional condensation and partial hydrolysis of organochlorosilanes was performed for the first time. In the hydrolysis of diorganodichlorosilanes with either an excess or a deficiency of water, the homofunctional condensation of diorganosilanediols is not the main mode for the chemical assembling of oligoorganosiloxanes. The main intermediates in the route of oligoorganosiloxane formation during organochlorosilane hydrolysis are the incomplete hydrolysis products (organochlorohydroxysilanes). Experimental data suggest that the chemical assembling of oligoorganosiloxanes occurs via the mechanism of organochlorohydroxysilane heterocondensation under usually used conditions of organochlorosilane hydrolysis.