| 摘要 |
The invention concerns 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), said method consisting in bringing the silanes bearing the hydrolyzable groups in the presence of water, buffer solution and neutralizing agent, while stirring, then in separating the aqueous phase from the organic phase, which comprises the hydrolysis/condensation products, namely hydroxylated polyorganosiloxanes. Said method is characterized in that it consists in: (a) implementing intensively stirring means capable of 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 d32 less than 500 mu m; (b) and 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 between 0.5 and 2.0. |
