Thermodynamics of mixed micelle formation

Abstract

A new method of calculating the composition of mixed micelles in equilibrium with monomer of known composition is proposed. This technique applies the Gibbs-Duhem equation to be mixed micelle, which is treated as a pseudophase. The method needs only CMC data as a function of monomer composition, but is limited to binary surfactant systems. The proposed methodology is applied to cationic/cationic, cationic/nonionic, and anionic/nonionic surfactant pairs. The calculated monomer-micelle equilibrium is found to be very similar to that from ideal solution theory for the cationic/cationic system and to the much-used regular solution theory for the nonideal systems. © 1986.