PROCEDE DE PREPARATION DE SILICONES A FONCTION ESTER DE HAUTE PURETE

摘要

The invention concerns a method for preparing polyorganosiloxanes with high purity ester function (acetoxyalkyl or acetoxyalkenyl) consisting in: hydrosilylation between a hydrogenopolyorganosiloxane oil and an alpha -olefin alcohol; esterification of the resulting hydroxy-alkylated or hydroxy-alkenylated polyorganosiloxane with an acetyl halide; elimination of alpha olefin derivatives and the halohydric acid formed. The resulting polyorganosiloxanes with ester function (acetoxyalkyl or acetoxyalkenyl) have global siloxane alpha olefin unit and/or alpha olefin impurities contents corresponding to a number of alpha olefin groups for 100g of polyorganosiloxane with ester function less than 10<-3>.