Langmuir 13, 5762-5765 (1997).
Paul D.T. Huibers1 and Dinesh O. Shah
University of Florida, Center for Surface Science and Engineering, Department of Chemical Engineering, Gainesville, FL 32611-6005
1Current address: Dept. of Chemical Engineering, Massachusetts Institute of Technology, 66-317, Cambridge, MA 02139-4307
It is well known that certain mixtures of surfactants can provide better performance than pure surfactants for a wide variety of applications, and thus it is expected that enhanced solubilization of water in water-in-oil (w/o) microemulsions will also be achieved with certain surfactant mixtures. The formation of w/o microemulsions involves dissolving an aqueous phase into an oil phase, creating a transparent and thermodynamically stable suspension of droplets with diameters in the range of 10-100 nm. It is desirable to accomplish this with a minimum amount of surfactant, and in order to achieve this goal, mixtures of surfactants can be used. We intend to address different surfactant mixtures that exhibit synergism in the solubilization of water in w/o microemulsions, showing the existence of at least two different mechanisms of synergism. The model system is composed of nonylphenyl ethoxylate as the surfactant and cyclohexane as the oil phase.