Surface rheology as a tool for the investigation of processes internal to surfactant adsorption layers.

The description of adsorption at liquid interfaces has been largely improved after incorporation into models of dynamic processes internal to the adsorption layers, such as surfactant re-orientation, aggregation and chemical reactions. Evidence for most of these processes has been given by qualitative studies utilising direct imaging techniques or by tensiometric investigations. These processes strongly influence the dilational rheological features of the adsorption layer, i.