Experimental technique to study adsorption kinetics

The drop methods, drop volume, drop shape and drop pressure, seem to be the most general ones, and they can usually be run, after small modification, with bubbles. These methods are applicable to both liquid-liquid and liquid-gas interfaces and need only small amoxmts of solvent and solute. In addition, the temperature control is easily arranged, even at higher temperatures. 

For dynamic adsorption studies several methods are suitable. The selection of a certain method depends on the experimental conditions, temperature and time interval, of the investigations to be performed. These experimental conditions are governed by the surface activity of the surfactant or polymer under study and its concentration. Some characteristics of dynamic surface tension methods are summarised in Table 5.2. 

The accuracy of all methods, over time intervals from several seconds to hours, is usually 0.1 mN/m. Special instruments enable measurements in the millisecond time scale. Such studies are performed with less accuracy, sometimes of the order of 1.0 mN/m. 

Before describing the experimental set-ups and interpreting the data on the basis of actual theories, the main prerequisite of interfacial studies is discussed the quality of the object under investigation. The most powerful technique is unable to yield reasonable results, if the 

Characteristics of dynamic surface and interfacial tension methods 

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