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

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.