Quantitatively Accurate Theory to Predict Adsorbed Configurations of Surfactants at Polar Surfaces

Surfactant molecules adsorb on polar surfaces in various morphologies, such as planar, spherical and cylindrical. So far, there is no encompassing theoretical framework that related molecular properties to the adsorbed morphologies. We have developed a theoretical model that is able to predict adsorbed morphologies of surfactant molecules on polar surfaces given their geometry and strength of interactions with the surface. We show, via coarse-grained simulations, that our theoretical model is quantitatively accurate in predicting the adsorbed configurations. Specifically, our model accurately predicts that linear-shaped surfactants adsorb either as a self-assembled monolayer or as stripes on the surfaces, depending on the relative interaction strengths of the polar head group and the alkyl tails with the surface. Our model correctly predicts the formation of different cylindrical and spherical configurations of the adsorbed asymmetrically shaped surfactant molecules.