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Polyelectrolyte Adsorption on Charged Substrate

Chi-Ho Cheng·Pik-Yin Lai
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Abstract

The behavior of a polyelectrolyte adsorbed on a charged substrate of high-dielectric constant is studied by both Monte-Carlo simulation and analytical methods. It is found that in a low enough ionic strength medium, the adsorption transition is first-order where the substrate surface charge still keeps repulsive. The monomer density at the adsorbed surface is identified as the order parameter. It follows a linear relation with substrate surface charge density because of the electrostatic boundary condition at the charged surface. During the transition, the adsorption layer thickness remains finite. A new scaling law for the layer thickness is derived and verified by simulation.

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Chi-Ho Cheng, Pik-Yin Lai. 2003-12-09. Polyelectrolyte Adsorption on Charged Substrate. https://doi.org/10.1063/1.1764122

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