MORPHOLOGY AND INVERSION OF DISPERSIONS OF 2 FLUIDS IN SYSTEMS OF 3 AND 4 THERMODYNAMIC DIMENSIONS

The morphologies and inversions of emulsions formed by pairs of conjugate liquids in the amphiphile/oil/brine system C4H9OC2H4OH/n-C10H 22/aqueous 10 mM NaCl were determined as a function of phase volume fraction by electrical conductivity measurements at temperatures below, between, and above the lower and upper critical end-point temperatures. In all cases the emulsions obeyed Ostwald's stereometric hard-sphere model semiquantitatively by inverting when the volume fraction of the internal phase became too large. A model diagram for the morphologies and inversions of dispersions of conjugate dense-fluid phases has been constructed and superimposed on the model phase diagram. It is predicted that this diagram and its extension to systems of four thermodynamic dimensions will prove to be generally valid and that, contrary to ubiquitous statements in the literature, the conjugate phase with the greater surfactant concentration is not always the continuous phase.