Fast exchange of alcohol molecules between micelles and surrounding solution in aqueous micellar solutions of ionic surfactants

Abstract

In the presence of alcohol, aqueous micellar solutions of ionic surfactants with long alkyl chains show a relaxational excess ultrasonic absorption characterized by a single relaxation frequency f R . The dependence of f R and of the ultrasonic relaxation amplitude R on various parameters can be readily explained by assigning the observed relaxation process to the fast exchange of alcohol molecules between micelles and surrounding solution. A quantitative treatment of this relaxation process should yield thermodynamic and kinetic information on the exchange of alcohol molecules between micelles and surrounding solution.