Spontaneous emulsification: relation to microemulsion phase behaviour

We present an experimental study of spontaneous emulsification of a surfact ant solution brought into contact with a pure oil. Because vescicles are pr esent in the surfactant solution, the dynamics can be followed directly usi ng phase contrast microscopy. The study is performed in a microemulsion for ming system for which the phase diagram is known. The results can be relate d to the equilibrium phase behaviour of the oil/water/surfactant system, an d are discussed in the light of existing models of spontaneous emulsificati on. (C) 1999 Elsevier Science B.V. All rights reserved.