STABILITY OF OSMOTICALLY COMPRESSED EMULSIONS IN THE PRESENCE OF IONIC SURFACTANTS

The stability of concentrated monodisperse emulsions, in the presence of ionic surfactants, is theoretically studied. We show that the criti cal disjoining pressure, above which coalescence is experimentally fou nd (Bibette, J.; et al. Phys. Rev. Lett. 1992, 69, 2439; Bibette, J. L angmuir 1992, 8, 3180) can be directly accounted from a simple DLVO th eory and agrees with the available experimental results even without u sing any adjustable parameter. Consequently it becomes more plausible through these results that the rupturing step requires an energy barri er to be overtaken, this step would be the limiting step in the case o f ionic layers.