Modeling Micellization and Interfacial Tension of Nonionic Surfactants using Dissipative Particle Dynamics

We use Dissipative Particle Dynamics (DPD) to simulate thermodynamic behavior of nonionic surfactants. In particular, we study the micellization of linear alkylethoxylates (CH$_{3}$-[CH$_{2}$]$_{n-1}$-O-[CH$_{2}$-CH$_{2}$-O]$_{m}$H or C$_{n}$E$_{m)}$ in water, as well as the influence of these surfactants on the oil-water interfacial tension. We demonstrate that for surfactants with n = 6, the onset of micellization in water occurs when the total surfactant concentration is on the order of 1{\%}, in agreement with experimental data and Quantitative Structure-Property Relationship (QSPR) models. We also simulate the dependence of dynamic and equilibrium interfacial tension in water/hexadecane/surfactant ternary mixture on the surfactant concentration and investigate the influence of micelle formation on the interfacial tension.