Micellization of gemini surfactant with dibenzyl ether spacer in water–organic mixed media

Abstract

The aggregation behavior and thermodynamics of gemini surfactant N,N′-(((1,4-phenylenebis(methylene))bis(oxy)) bis(ethane-2,1-diyl))bis(N,N-dimethyldodecan-1-aminium) (12-B-12) in a binary mixed solvent of water and organic solvents [1,4-dioxane (DO) and ethylene glycol (EG)] within the temperature range of 25°C to 40°C were investigated by the conductivity method. Micellization was delayed with the addition of organic co-solvent; consequently, a progressive increase was observed in critical micelle concentration (cmc), Gibbs free energy of micellization (ΔGm0), and Gibbs free energy of transfer (ΔGtrans0). 12-B-12 was found to be more prone to micellization in EG–water than in DO–water because of the lower cmc, more significantly negative ΔGm0, and less significantly positive ΔGtrans0. Enthalpy–entropy compensation was also investigated.