ABSTRACT
I. INTRODUCTION Microemulsions are thermodynamically stable onephase solutions of immiscible substances such as water (or another polar component, e.g., formamide) and oil (hydrocarbon, fluorocarbon, or silicone) that self-assemble in the presence of one or more surfactants into a wide range of microstructures. Depending on the temperature, composition, molecular architecture, and hydrophobicity or hydrophilicity of these components, various microstructures can exist. As the oil-to-water ratio is increased, a progression of microstructures, ranging from oil-swollen micelles dispersed in water to bicontinuous structures and finally to water-swollen micelles dispersed in oil, is typically observed. Furthermore, the oil-or water-swollen micelles can adopt spherical, ellipsoidal, or rodlike geometries. With some exceptions, microemulsions are optically transparent because the length scales of the oil and water domains are usually less than 10 nm. The rich variety of microstructures possible within microemulsions have made them the subject of great scientific and practical interest.
