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Published on: February 6, 2014
The effect of shear flow on the Helfrich interaction in lyotropic lamellar systems
1Polymer IRC and Department of Physics & Astronomy, University of Leeds, Leeds LS2 9JT, UK. physwm@irc.leeds.ac.uk
Abstract:
We study the effect of shear flow on the entropic Helfrich interaction in lyotropic surfactant smectic fluids. Arguing that flow induces an effective anisotropic surface tension in bilayers due to a combination of intermonolayer friction, bilayer collisions and convection, we calculate the reduction in fluctuations and hence the renormalised change in effective compression modulus and steady-state layer spacing. We demonstrate that non-permeable or slowly permeating membranes can be susceptible to an undulatory instability of the Helfrich-Hurault type, and speculate that such an instability could be one source of a transition to multilamellar vesicles.
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