FORMATION AND PROPERTIES OF REVERSED MICELLES OF AEROSOL OT CONTAINING UREA IN THE AQUEOUS POOL

The effect of urea on the properties of reversed micelles was investigated using sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in hexane. Using quasielastic light scattering and conductivity measurements, we demonstrated the formation of reversed micelles of AOT containing up to 10 M urea in the water pool at low aqueous volume fractions (phi(w)). Transition to bicontinuous phases are obtained at progressively lower phi(w) as the concentration of urea in the water pool is increased. In a particular urea concentration (5.0 M in the aqueous pool) the conductivity of the solution decreases with temperature between 10 and 50-degrees-C. The properties of the urea-containing water pool of the AOT micelles were probed measuring the rates of excited- and ground-state proton transfer reactions with the prototropic probe 8-hydroxy-1,2,6-pyrenetrisulfonate. The proton transfer rates in reversed AOT micelles in hexane containing urea are similar to the rates obtained with the same probe in bulk aqueous solution.