Bulk-Solution Properties of CpyCl/CTABr a Mixed Surfactant System in the Presence of Nonionic Hydrotropes

The current research work centred on the micellization of binary system of Cetylpyridinium chloride (CpyCl) and cetyltrimethylammonium bromide (CTABr) in the absence and presence of nonionic hydrotropes (i.e urea and resorcinol) using conductometric technique. The critical micelle concentrations (CMC), at different mixed mole fraction of mixed surfactant were evaluated. Activity coefficient, ideal CMC, micellar mole fraction, interaction and thermodynamic parameters were obtained using theoretical Clint and Rubingh models.Addition of hydrotropes lowered the CMC values than the ideal CMC values and the individual components which is an indication of positive synergistic interaction in CpyCl/CTABr mixed micelle formation. The interaction parameter values were all negative, signifying strong interaction between the mixed surfactant. The evaluated thermodynamic parameters were all negative, indicating spontaneity and stability of the mixed micelle formed