Excluded volume effects in polymer brushes at moderate chain stretching

TL;DR

This paper introduces a strong stretching approximation for self-avoiding polymer brushes, improving predictions of density profiles and end monomer distributions at moderate chain stretching compared to previous Gaussian-based models.

Contribution

It develops a novel strong stretching approximation that accounts for finite extensibility, providing more accurate descriptions of polymer brushes at moderate stretching.

Findings

Better agreement with simulation data for density profiles

More accurate end monomer distribution predictions

Outperforms Gaussian elasticity models at moderate stretching

Abstract

We develop a strong stretching approximation for a polymer brush made of self-avoiding polymer chains. The density profile of the brush and the distribution of the end monomer positions in stretching direction are computed and compared with simulation data. We find that our approach leads to a clearly better approximation as compared to previous approaches based upon Gaussian elasticity at low grafting densities (moderate chain stretching), for which corrections due to finite extensibility can be ignored.