| Abstract
| - A mathematical model describing the concentration polarization in the three-phase contact region during theLangmuir−Blodgett deposition process is developed. It is shown that the stationary deposition is only possiblewhen, in additional to convective fluxes, electrodiffusion ionic fluxes and corresponding concentration gradientsare developed in the system. At a sufficiently low withdrawal speed, the occurring diffusion and migrationionic fluxes restore the steady-state ionic balance. As well, electric charge is accumulated in close vicinity tothe three-phase contact line to produce a stationary electric field. The concentration polarization affects theparameters of the deposition process (dynamic contact angle, work of adhesion, maximum deposition rate) aswell as morphology, composition, and structure of the deposited monolayer. When the withdrawal speedexceeds a critical value, the transport of counterions becomes insufficient to compensate interfacial charge inclose vicinity to the three-phase contact line. Consequently, the electrostatic repulsion between the monolayersbecomes sufficiently strong to disrupt the deposition process. The latter can result in meniscus instability.The proposed mechanism correlates with some experimental observations.
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