Neues über Mikroemulsionen

On the basis of a literature review covering the period from 1986‐1989, recent developments in the field of microemulsion research are outlined. The paper deals with results and statements obtained from instrumental physical or physico‐chemical methods, theoretical treatments and special applications, altogether mostly relevant to the progress of understanding this particular state of liquid mixtures. Predominantly concerned are systems consisting of either nonionic surfactant, water, and oil component or ionic surfactant alkanol, water, and oil component; but also new compounds of microemulsion systems are considered. Microstructural details and microdynamics have been recognized with the aid of modern versiona of laser‐light, x‐ray, and neutron scattering, molecular spectroscopy, different relaxation methods, electron microscopy, and using classical methods, e.g. viscosity, electric conductance, surface tension measurement. Both phase behaviour and phase equilibria including tricriticalities are well‐suited macroscopic properties to border microemulsion composition regions. Statistical mechanics as well as molecular simulation procedures have provided proper instruments for a quantitive interpretation of the microemulsion state. The applications of microemulsions discussed refer to the preparation of selective solvent media and to the realization of alternative separation principles: e.g. liquid membranes in multiple emulsion configuration or micellar‐enhanced ultrafiltration.