Model for simulations of the CnEm nonionic surfactant family derived from recent experimental results

Abstract

Many coarse grained models exist for simulations of micelle forming surfactants of the CnEm family (H[CH2]n-[OCH2CH2]m-OH). However, it has been a challenge for models to accurately reproduce both the critical micelle concentration (CMC), and the mean aggregation number (Nagg) trends with respect to the surfactant concentration and with respect to the lengths of the hydrophobic and hydrophilic molecular segments. Using carefully developed experimental data on a range of compounds from the CnEm family, and ForceBalance, a software package for force field fitting now commonly used for atomistic force field development, we have produced a simple model that accurately reproduces these important trends in the context of dissipative particle dynamics (DPD) simulations. The presentation will include a comparison of this force field with another one produced in our laboratory, that was trained on water-octanol partition coefficient data.