Study on the Complex System of Sodium Lauryl Diphenyl Ether Disulfonate and Dodecyl Dimethyl Hydroxyethyl Ammonium Chloride

Abstract

AbstractSurface chemical properties of the mixed system of sodium lauryl diphenyl ether disulfonate (C12-MADS, an anionic surfactant with double hydrophilic groups) and dodecyl dimethyl hydroxyethyl ammonium chloride (K3, a cationic quaternary ammonium surfactant) along with different proportion have been studied at 298 K and 318 K. Synergistic parameters of the mixture in the mixed micelles and the mixed adsorption layer were also calculated by using the regular solution theory. The composition of the mixed micelles and of the mixed adsorption layer was obtained. The results show that the surface chemical properties of C12-MADS/K3 mixture are better than either of single system, and when the solution ratio (α1 = [n (K3)/n (C12-MADS + K3)]) is 0.7 and 0.9, the surface tension curve has a double inflection point which indicates a synergistic effect between the surfactant molecules. The complex system showed a strong synergistic effect in the mixed adsorption layer and the mixed micelles. The mixed system of C12-MADS/K3 has synergism in surface tension reduction effectiveness, surface tension reduction efficiency and mixed micelle formation. When α1 is 0.67, the synergistic effect is the strongest.