Microemulsions: An overview

In the past twenty five years, microemulsions have been the focus of extensive research worldwide due to their importance in a variety of technological applications. These applications include enhanced oil recovery, combustion, cosmetics, pharmaceuticals, agriculture, metal cutting, lubrication food, enzymatic catalysis, organic and bio-organic reactions, chemical synthesis of nanoparticles etc. The basic purpose of this review is intended to provide the most important features of microemulsions and their applications. Emphasis is placed on recent works, however, the reference list is by no means complete. In order to limit the size of the review, a more or less arbitary selection has been made with respect to examples chosen from literature. The review is started with a brief introduction and focussed with definition, structure, type, formation characteristics, stability, phase behavior and the effect of additives, pressure, temperature on the phase behavior of microemulsion. In addition, the physicochemical properties, state of water in the micropool, transport (electrical and hydrodynamic) behaviors, thermodynamics of formation, solubilization parameters, and uses and applications of microemulsions have been briefly presented.