Boundary Condition of Polyelectrolyte Adsorption

TL;DR

This paper investigates how boundary conditions for polyelectrolyte adsorption vary with charge density and interaction strength, revealing different regimes where classical conditions apply or need modification.

Contribution

It introduces a modified boundary condition for highly charged polyelectrolytes, extending the understanding of adsorption behavior under electrostatic dominance.

Findings

Boundary condition matches neutral polymer adsorption for weakly charged polymers.

Electrostatic boundary condition requires modification for highly charged polymers.

Different regimes depend on the dominance of short-range attraction or electrostatic interaction.

Abstract

The modification of the boundary condition for polyelectrolyte adsorption on charged surface with short-ranged interaction is investigated under two regimes. For weakly charged Gaussian polymer in which the short-ranged attraction dominates, the boundary condition is the same as that of the neutral polymer adsorption. For highly charged polymer (compressed state) in which the electrostatic interaction dominates, the linear relationship (electrostatic boundary condition) between the surface monomer density and the surface charge density needs to be modified.