Experimental methods, interfacial processes interface study

The equilibrium and dynamics of adsorption processes from micellar surfactant solutions are considered in Chapter 5. Different approaches (quasichemical and pseudophase) used to describe the micelle formation in equilibrium conditions are analysed. From this analysis relations are derived for the description of the micelle characteristics and equilibrium surface and interfacial tension of micellar solutions. Large attention is paid to the complicated problem, the micellation in surfactant mixtures. It is shown that in the transcritical concentration region the behaviour of surface tension can be quite diverse. The adsorption process in micellar systems is accompanied by the dissolution or formation of micelles. Therefore the kinetics of micelle formation and dissociation is analysed in detail. The considered models assume a fast process of monomer exchange and a slow variation of the micelle size. Examples of experimental dynamic surface tension and interface elasticity studies of micellar solutions are presented. It is shown that from these results one can conclude about the kinetics of dissociation of micelles. The problems and goals of capillary wave spectroscopy of micellar solutions are extensively discussed. This method is very efficient in the analysis of micellar systems, because the characteristic micellisation frequency is quite close to the frequency of capillary waves. 

The study of surfaces and interfaces has always been hampered by the search of appropriate experimental tools. Optical surface second-harmonic generation (SSHG) has been shovm to be a powerful method and has thus been widely applied over the last decades in surface science. Phenomena like adsorption processes, surface reconstruction or interfacial chemical reactivity have been investigated at both solid and liquid surfaces and have already been extensively reviewed in the past [1-5]. At Uquid/ liquid interfaces experimental results are far less numerous, despite the growing interest for these interfaces which... 

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