Elasticity of Foam Cell Elements

Since the boundary of a foam cell is a multilayer film [429], the elasticity of this shell is many times larger than the elasticity of the adsorption layer. 

For higher concentrations of surfactants in the adsorption layer, surface pressure, as well as some cohesive forces, may act between the adsorbed molecules. The adsorption layer acquires some additional strength, whose maximum value corresponds to the state of an incompletely filled layer with inclined position of adsorbed molecules whose hydrophobic tails interlace each other [9]. Moreover, the elasticity of a strongly developed surface may decrease if the system contains a limited amount of surfactants [125]. 

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