PREPARATION OF SILICONE RESINS

摘要

In a process for the preparation of a solution of a stable silicone resin comprising SiO4/2 units and units selected from RsiO3/2, RR'SiO2/2, and RR'2SiO1/2 units, where R is an alkyl, alkenyl, substituted alkyl, cycloalkyl, aryl or aralkyl group imparting desired physical or chemical properties to the resin, for example a thermally labile group, and each R'is a different alkyl, substituted alkyl, cycloalkyl, aryl or aralkyl group, or a hydrogen atom, a hydrosiloxane resin comprising HSiO3/2 units and the said units selected from RsiO3/2, RR'SiO2/2, and RR'2SiO1/2 units is treated with a base to condense at least some of the HsiO3/2 units to form SiO4/2 units. The base is preferably a solution of an alkali metal salt of a weak acid such as sodium acetate.