Experimental results of relaxation studies

The present section is dedicated to a selection of experimental results obtained by different techniques. So far there are only few experiments performed to compare results of different methods for the same surfactant solution, as in Chapter 5 with respect to adsorption kinetics investigations. Thus, experimental data have to be interpreted with regard to the specific experimental conditions. Several experimental and theoretical problems of surface relaxations where discussed recently (Miller et al. 1994a) and experimental examples were given in order to demonstrate the importance of such studies. 

This section aims to demonstrate the variety of relaxation studies performed with surfactant solutions. Results for single surfactant and surfactant mixtures as well as micellar solutions will be shown. A newly available technique for liquid/liquid interfaces is also discussed here. 

As mentioned above, only few comparisons of different techniques have been reported. For example, Jiang et al. (1992) studied the dilational elasticity of Triton X-100 adsorption layers with plane and cylindrical capillary wave. The results of the two measurements are given in Fig. 6.10. 

Although the experimental conditions and the theories differ from each other, the agreement between the results is excellent. 

Effective dilational elasticity of n-octanoic acid ( ) and dodecyl amine hydrochloride ( ) at 200 Hz, measured with a capillary wave technique according to Lucassen Hansen (1966) 

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