Polyelectrolyte Layer-by-Layer Assembly from Self-Consistent Field Calculations

TL;DR

This study models the layer-by-layer assembly of polyelectrolytes, revealing growth patterns, internal structure, and effects of various parameters, aligning well with experimental observations.

Contribution

It introduces a self-consistent field calculation approach to model multilayer assembly, providing detailed insights into structure and growth dynamics.

Findings

Exponential growth in initial layers transitions to linear growth.

Multilayers exhibit a three-zone internal structure.

Surface charge, salt, and solvent quality influence multilayer properties.

Abstract

We have modeled the layer-by-layer assembly process of flexible polyelectrolytes on flat surfaces. The multilayer has a three-zone structure. An exponential growth is found for the first several layers, followed by a linear growth for subsequent layers evolving towards a steady state. While adjacent layers are highly interpenetrating, stratification can be seen for every four or more layers. The effects of surface charge density, bulk salt concentration, and solvent quality on the thickness and internal structure of the multilayer are also studied. Our results agree with experimental findings.