Spontaneous emulsification

Abstract

Spontaneous emulsification may occur when immiscible liquids in non-equilibrium conditions are in contact. This phenomenon is triggered by gradients of chemical potential between the phases, which under certain conditions lead to negative values of free energy of emulsification. A summary of background information on spontaneous emulsification is first presented with emphasis on proposed mechanisms. It follows a description of recent developments, in both surfactant-free and surfactant systems. Applications based on the use of spontaneous emulsification to produce delivery systems and nanostructured materials with improved properties in a cost-effective way are also described.