| abstract |
A method for hydrolyzing/condensing, by acid catalysis, silanes bearing hydrolyzable groups, preferably halogenosilanes and more preferably still chlorosilanes, in a polyphase reaction medium (preferably biphasic), includes contacting the silanes bearing the hydrolyzable groups with water, buffer solution and neutralizing agent, while stirring, then in separating the aqueous phase from the organic phase, which contains the hydrolysis/condensation products, namely hydroxylated polyorganosiloxanes; such method is characterized by (a) employing intensively stirring means producing, in the reaction medium, an agitation at least equivalent to that induced by a shearing corresponding to that provided by a rotor whereof the peripheral speed is not less than 8 m.s −1 , preferably not less than 10 m.s 1 , and more preferably still ranging between 15 and 20 m.s −1 , enabling thus organic phase droplets to be formed, of d 32 less than 500 μm; and (b) ensuring that the silanes/aqueous phase mass fraction is not less than 0.05, preferably not less than 0.10, and more preferably still ranging from 0.5 to 2.0. |