Method for emulsifying heat-sensitive silicones emulsion without grinding
申请人:Rhodia Chimie
公开号:US06660778B1
公开(公告)日:2003-12-09
The invention concerns a method for emulsifying, without grinding, a silicone in water in the presence of a surfactant, at a temperature less than 60° C. and under shearing at less than 100 s−, comprising steps which consist in: a) preparing a primary oil-in-water emulsion including said surfactant and said silicone under shearing at less than 100 s−, by adding an aqueous phase to an oily phase comprising said silicone; b) enriching the resulting emulsion with an enriching oily phase comprising said silicone by mixing, under shearing at less than 100 s−, and c) if required, repeating one or several times the operation at step b) until the desired concentration in surfactant and/or silicone in the final emulsion is obtained and/or until the desired particle size distribution is obtained.
The reaction of aryl fluorides with silyl reagents has been shown to be efficiently promoted by tetrabutylammoniumfluoride, providing aryl ethers with good to excellent yields under solvent-free conditions. The efficiency of this reaction was demonstrated by the compatibility with aldehyde, nitro, cyano and acetyl groups. Moreover, the rigorous exclusion of air/moisture was not required in these transformations