Evaluation of the alcohol-mediated interaction between micelles using percolation processes of reverse micellar systems

The effectiveness of the addition of small amount of alcohols on the micellar-micellar interaction of the reverse micellar systems (RVMS) has been studied by the quantitative analysis of its percolation phenomena. By adding various alcohols to RVMS, the alcohol-induced micellar-micellar interaction was evaluated and correlated based on the role of each group constituting the alcohol molecule to the percolation process, namely, the hydrocarbon group, hydroxyl group, and halogen substituents. Among these groups, the hydrophobic hydrocarbon groups suppress the micellar-micellar interaction proportionally to their chain number, while hydrophilic hydroxyl groups enhance it. Halogen groups also suppress the micellar-micellar interaction depending on their number and species. These results suggest that the effect of alcohols can be explained by the additive contributions of each group of alcohol, which are proportional to the accessible surface area. We have constructed equations for estimating the effect of alcohols on the micellar-micellar interactions, which should also be useful for predicting various interesting effects of alcohols and for evaluating the unified role of various alcohols on micelles. (C) 1999 Elsevier Science S.A. All rights reserved.