摘要 |
Described is a method of preparing microemulsions of organopolysiloxanes, by copolymerizing a cyclic siloxane and a polyfunctional silane, in an aqueous medium containing a nonionic surfactant, an anionic or cationic surfactant, and a catalyst, until the desired increase in molecular weight is obtained. The invention resides in controlling the gel content of the organopolysiloxanes in the microemulsion by control of the concentration of silane and concentration of silanol in the resulting organopolysiloxane, such that a functionality ratio phi results in formation of a gel-free polymer molecular weight distribution of finite organopolysiloxane species in the microemulsion.
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