Pattern formation in thin liquid films with charged surfactants.
The dynamic evolution of positively charged surfactants at the interface of a thin film resting atop a negatively charged base is investigated. The lubrication approximation is used to develop coupled equations governing the dynamic evolution of such a system in the presence of charge effects coupled with van der Waals forces. The equations are investigated numerically and analytically, and, for certain parameter ranges, pattern formation is observed reminiscent of that accompanying thermocapillary-driven thin films. Spatial nonuniformities in the charge of the underlying substrate are also studied as a possible tool for film rupture wavelength selection.
Warner
M R E
MR
Department of Mathematics, Imperial College London, South Kensington, London, SW7 2AZ, UK.
Craster
R V
RV
Matar
O K
OK