The Effect of Mixtures and Additives on Dissolving Surfactant Lamellar Phases

Understanding the dissolution process of surfactant solutions is important in formulated product design processes. The main goal of this study is to gain further insights into how additives and mixtures affect surfactant dissolution processes. To achieve this goal dissipative particle dynamic simulations (DPD) were used. Lamellar phases at 80% volume of surfactant were initially equilibrated with water. After reaching an equilibrium state the dissolution simulations were carried out for different surfactant mixtures. To track the dissolution process different metrics were used, including visual analysis, local concentration analysis, diffusion and cluster size calculations. Results show that by having a mixture of surfactants, the diffusion of the micelles is not affected only by the size of the micelles as in pure surfactant systems, but there is also an effect due to composition of the micelles. When oil is added to a surfactant system the system acts like a longer chain surfactant system, but only when the chain of oil becomes sufficiently long.