Abstract
Surfactants form various self-organizing structures in solution. The relationship between formation of self-organizing structures, especially, microemulsions, high-internal-phase-ratio-emulsions (HIPREs), and reverse vesicles and the phase behavior in water/nonionic surfactant/oil system is reviewed.
Ultra-low interfacial tensions and maximum solubilization are attained in microemulsion systems when the HLB (Hydrophile-Lipophile Balance) of surfactant is optimum in a given systems These properties are used for practical applications such as enhanced oil recovery, detergency, etc.
The new method to form HIPRE is discussed, In this method, O/W microemulsions are spontaneously changed to HIPRE by changing temperature. Finally, we describe the recent result of reverse vesicles.
