We have recently shown that surfactant-free micelles exist in ternary octanol/ethanol/water mixtures for compositions where the ternary solution is stable, but close to the line of phase separation. In these micelle-like aggregates, ethanol plays the role of a mediating octanol hydration and is enhanced at the interface between the polar and nonpolar pseudo phases.
In this presentation, we have a closer look at the origin of ethanol’s interfacial activity. For this purpose, we perform atomistic molecular dynamics simulations of planar octanol/water interfacial systems with different amounts of ethanol present. These simulations give insight into the energetic components that determine ethanol’s behaviour at the interface. The simulation results point to a complex interplay of van der Waals and Coulomb interactions which determine the distribution and surface behaviour of ethanol.
