Synergistic interaction of Gemini surfactant pentanediyl-1,5-bis(dimethylcetylammonium bromide) with conventional (ionic and nonionic) surfactants and its impact on the solubilization

The structure of Gemini surfactants makes them potentially useful candidates in terms of their performance, particularly in mixed micelles for different surfactant applications. We have studied mixed micellization and surface properties of binary mixtures of cationic Gemini pentanediyl-1,5-bis(dimethylcetylammonium bromide) (G5, 16-5-16) with conventional cationic cetylpyridinium chloride (CPC), anionic sodium bis(2ethylhexylsulfosuccinate) (AOT), and nonionic polyoxyethylene 10 cetyl ether (Brij 56) in detail by conductometric and tensiometric methods. The interfacial and bulk behaviors were investigated using theoretical models of Clint, Rubingh, Rosen, and Maeda to explain and compare the results of binary mixtures of G5 with the conventional surfactants. The synergism was observed in all the binary systems in the micelle as well as at the interface with expansion of molecular area per molecule. Greater synergistic interaction in the micelles has been found to reduce the solubilizing capacity towards polyaromatic hydrocarbons (PAHs).