Behavior of rod-like polyelectrolytes near an oppositely charged surface

TL;DR

This study uses Monte Carlo simulations to analyze how highly charged rod-like polyelectrolytes interact with oppositely charged surfaces, revealing their adsorption behavior and the effects of various physical parameters.

Contribution

It provides a detailed microstructural analysis of rod-like polyelectrolytes near charged surfaces, highlighting the impact of chain length, surface charge, and image forces, which was less explored before.

Findings

Rod-like polyelectrolytes adsorb more effectively than flexible chains.

Image forces reduce adsorption at low dielectric constants.

Chain orientation and charge distribution depend on surface and chain parameters.

Abstract

The behavior of highly charged short rod-like polyelectrolytes near oppositely charged planar surfaces is investigated by means of Monte Carlo simulations. A detailed microstructural study, including monomer and fluid charge distribution, and chain orientation, is provided. The influence of chain length, substrate's surface-charge-density and image forces is considered. Due to the lower chain-entropy (compared to flexible chains), our simulation data show that rod-like polyelectrolytes can, in general, better adsorb than flexible ones do. Nonetheless, at low substrate-dielectric-constant, it is found that repulsive image forces tend to significantly reduce this discrepancy.