MICELLAR SURFACE-CHARGE MODIFICATION FOR REGULAR SOLUTION THEORY - APPLICATION TO MIXED SYSTEM OF CATIONIC FLUOROCARBON-NONIONIC HYDROCARBON SURFACTANTS

A micellar surface charge modification for the regular solution theory was performed by considering the counterion bind effect. For mixed mi celles of cationic fluorocarbon-nonionic hydrocarbon surfactants, this modified equation can be tested by measuring the mixed cmc, surface p otential, aggregation number, and molar volumes. The mixed cmc curves are well fitted with the calculated curves by the modified equation as a function of cationic surfactant molar fraction. The interaction bet ween the surfactants is not so repulsive as expected from the regular solution theory. In addition, the mixed micelles with various mole fra ctions exist in a wide mixing region and the size of mixed micelles ha ving charge is fairly small.