Dissipative particle dynamics simulations of surfactant CTAB in ethanol/water Mixture

Abstract

Dissipative particle dynamics is used to study the self-assembly and surface tension of a surfactant cetyl trimethylammonium bromide (CTAB) in ethanol/water mixture. With a simple spring and bead model, we investigate how ethanol influences the aggregation structure and the ability to reduce the surface tension of CTAB. It is not the surfactant total concentration, but the bulk concentration, that should be employed to describe the surfactant's properties accurately. The results show that ethanol may produce inhibition for micellar growth and enlarge the critical micelle concentration of CTAB. We further discuss the impact of the conservative international parameter between head and head (), which has a close relationship to counterions. It is found that the decrease of has the effect to enlarge the efficiency of CTAB.