Spherical Polymer Brushes Under Good Solvent Conditions: Molecular Dynamics Results Compared to Density Functional Theory

TL;DR

This study compares Molecular Dynamics simulations and density functional theory to analyze the structure and behavior of spherical polymer brushes under good solvent conditions, revealing insights into chain conformations and theoretical model applicability.

Contribution

It provides a comparative analysis of Molecular Dynamics and density functional theory for spherical polymer brushes, highlighting structural properties and model limitations.

Findings

Monomer density profiles show crossover to star polymer limit with increasing chain length.

Distribution of polymer ends and chain dimensions are characterized.

Theoretical tools' applicability range is identified.

Abstract

A coarse grained model for flexible polymers end-grafted to repulsive spherical nanoparticles is studied for various chain lengths and grafting densities under good solvent conditions, by Molecular Dynamics methods and density functional theory. With increasing chain length the monomer density profile exhibits a crossover to the star polymer limit. The distribution of polymer ends and the linear dimensions of individual polymer chains are obtained, while the inhomogeneous stretching of the chains is characterized by the local persistence lengths. The results on the structure factor of both single chain and full spherical brush as well as the range of applicability of the different theoretical tools are presented. Eventually an outlook on experiments is given.