1. The Direct Adsorption of Micelles to a Clean Air/Water Interface
Charles Maldarelli, Department of Chemical Engineering, City College of New York
A theory has been formulated to describe the direct adsorption of micelles from an aqueous solution onto a clean air/water interface. Dynamic surface tension experiments, using the pendant bubble technique and the polyethoxylated surfactant CH3(CH2)13(OCH2CH2)6OH, have been undertaken to measure the kinetic parameters of the model by comparing the solutions of the model and the measured tensions. The model predicts two regimes, depending on the micellar concentration. In the low concentration regime, a micelle free zone form underneath the surface (bottom left), while at higher micellar concentrations micelles are transported directly up to the surface (bottom right). Very good agreement is obtained between theory and experiment.