Foams micellar structural forces

Using this model, two important conclusions may be made concerning the stability of a foam. Firstly, after a certain surfactant concentration (above the cmc) the stability of the foam (or emulsion) film will increase due to the additional stabilizing force of the micellar periodic structure in the film. Secondly, increasing the electrolyte concentration will decrease the repulsive forces between the micelles in the film thus inhibiting the formation of a micellar periodic structure in the film core. The effect of electrolyte will of course differ for anionic and nonionic surfactants. 

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