TEMPERATURE-DEPENDENCE OF EMULSION MORPHOLOGIES AND THE DISPERSION MORPHOLOGY DIAGRAM

The recently constructed "dispersion morphology diagram" predicts that for amphiphile/oil/water systems there exists a range of concentrations within which only OL/AQ ("oil-in-water") emulsions form and another range of concentrations for which the emulsion morphology is always AQ/OL ("water-in-oil"), regardless of whether the temperature is below the lower critical end-point temperature, above the upper critical end point, or between these two temperatures. These predictions contradict the PIT (phase inversion temperature) idea, that below the PIT amphiphile/oil/water systems form only "oil-in-water" emulsions and above the PIT they form only "water-in-oil" emulsions. By using electrical conductivity measurements to determine the emulsion morphologies at different temperatures for systems for constant composition, we show for the system studied that the previous predictions of the dispersion morphology diagram are correct.