Viscosity thin electrical double layers

Because of the limited magnitude of surface tension gradients and absence of electric double-layer effects, the stabilization of foams in nonpolar liquids requires other ways of retarding the thinning of foam lamellae. These include the high liquid-phase viscosity that has been discussed earlier and increased surface viscosity because of presence of highly viscous or even rigid liquid-crystal films. 

Consider a thin liqmd Aim in air for which the Hamaker constant Ah is 5 x K)- erg and electrical double-layer effects are negligible. If viscosity is 1 cp, density is 1 g/cm. Aim thickness is 50 nm, and surface tension is 40 mN/m, And the wavenumbers and of the critical and fastest growing disturbances and the time factor (3 for growth of the latter using the inextmisible interface results given above. Compare with the corresponding results for a free interface in the inviscid approximation. 

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