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arXiv · cond-mat/0509157

Polyelectrolyte multilayer formation: electrostatics and short-range interactions

Adi Shafir·David Andelman
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Abstract

We investigate the phenomenon of multilayer formation via layer-by-layer deposition of alternating charge polyelectrolytes. Using mean-field theory, we find that a strong short-range attraction between the two types of polymer chains is essential for the formation of multilayers. The dependence of the required short-range attraction on the polymer charge fraction and salt concentration is calculated. For weak short-range attraction between any two adjacent layers, the adsorbed amount (per added layer) decays as the distance from the surface increases, until the chains stop adsorbing altogether. For strong short-range attraction, the adsorbed amount per layer increases after an initial decrease, and finally it stabilizes in the form of a polyelectrolyte multilayer that can be repeated many times.

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Adi Shafir, David Andelman. 2006-01-03. Polyelectrolyte multilayer formation: electrostatics and short-range interactions. https://doi.org/10.1140/epje%2Fe2006-00018-3

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