The anionic conventional surfactants effect on the nanostructures and microstructures properties in cationic Gemini surfactants aqueous solution

Abstract

The adsorption behavior at the liquid-air interface and aggregation characteristics were investigated in Gemini surfactants in aqueous media containing different concentrations of conventional ionic surfactants by surface tension and conductometry measurements. Also, the effects of anionic conventional surfactants (ACS) were studied on the size and transition from nanostructures to microstructures and vice versa. The free energy of the mixed micellization (ΔG° <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mic</sub> ) was obtained from the critical micelle concentration (CMC) and degree of counter ion dissociation (α) values. The differences in the free energies of micellization of Gemini surfactants between pure state and Gemini-ACS mixtures were calculated to monitor the influence of ACS on the micellization process. It has been observed when mole fraction of ACS increase, CMC and micellar ionization degree decrease. Also the surface excess concentration, Γ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> , increases and the minimum area per surfactant molecule, A <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">min</sub> , decreases when the amount of ACS in the mixture increases.