| 摘要 |
A method of stabilizing aqueous microemulsions against hydrolysis or phase separation of the active ingredient therein comprising buffer the microemulsion to acidic conditions using a surface active hydrophobic acid having a pKa of about 2-5, which have a hydrophobic group capable of entering micelles to preclude an undesired increase in electrolyte strength in the bulk aqueous medium. The method is particularly applicable to active ingredients which ordinarily hydrolyze under basic conditions, or precipitate in an acid medium buffered by conventional inorganic acids. An embodiment of the invention comprises an aqueous microemulsion of a carbamate ester which is stabilized against hydrolysis or precipitation at a pH of about 6.5 with a buffer of nonylphenyl ethoxylated phosphoric acid.
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