Universality in film stratification due to colloid crystal formation

Abstract

Experimental results with different colloidal systems (ionic and non-ionic micelles, swollen micelles, latex suspensions) are presented to demonstrate the universality of the phenomenon termed film stratification (stepwise thinning of liquid films). A general explanation of the phenomenon is proposed which assumes that the stratification is caused by the layer-by-layer expulsion of a colloid crystal-like structure formed by spherical particles (micelles, latex particles, etc.) inside the film. The effect of different factors on the stratification such as surfactant and electrolyte concentrations, temperature, etc. is explained from this viewpoint.