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arXiv · 1010.5083

Single polymer adsorption in shear: flattening versus hydrodynamic lift and corrugation effects

Andreas Serr·Christian Sendner·Florian Mueller·Thomas R. Einert·Roland R. Netz
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Abstract

The adsorption of a single polymer to a flat surface in shear is investigated using Brownian hydrodynamics simulations and scaling arguments. Competing effects are disentangled: in the absence of hydrodynamic interactions, shear drag flattens the chain and thus enhances adsorption. Hydrodynamic lift on the other hand gives rise to long-ranged repulsion from the surface which preempts the surface-adsorbed state via a discontinuous desorption transition, in agreement with theoretical arguments. Chain flattening is dominated by hydrodynamic lift, so overall, shear flow weakens the adsorption of flexible polymers. Surface friction due to small-wavelength surface potential corrugations is argued to weaken the surface attraction as well.

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Andreas Serr, Christian Sendner, Florian Mueller, Thomas R. Einert, Roland R. Netz. 2010-10-25. Single polymer adsorption in shear: flattening versus hydrodynamic lift and corrugation effects. https://doi.org/10.1209/0295-5075%2F92%2F38002

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