Phase behavior and interfacial curvature in water-oil-surfactant systems

The phase behavior of water-oil-surfactant systems follows general patterns. The driving force for the phase behavior has been identified as the variation of the mean curvature of the surfactant film with temperature. The minimum of interfacial tension accompanying the phase inversion has been shown to be caused by the mean curvature passing zero. These findings help increase our understanding of investigations in a number of other areas including the role of cosurfactants, phase inversion temperature, and hydrophilic-lipophilic balance for emulsion formation. Furthermore, new applications of microemulsions as reaction media and new formulations all make use of tuning the curvature of the amphiphilic film.