Self-Consistent-Field Study of Adsorption and Desorption Kinetics of Polyethylene Melts on Graphite and Comparison with Atomistic Simulations

TL;DR

This study develops a combined theoretical approach to predict adsorption and desorption rates of polyethylene melts on graphite, validated against molecular dynamics simulations, providing a new tool for understanding polymer-surface interactions.

Contribution

It introduces a self-consistent field and transition state theory-based method for estimating polymer adsorption/desorption rates, validated against atomistic simulations.

Findings

Predictions closely match molecular dynamics results for short chains.

Method effectively estimates rates for polymer melts on graphite.

Provides a computationally efficient alternative to detailed simulations.

Abstract

A method is formulated, based on combining self-consistent field theory with dynamically corrected transition state theory, for estimating the rates of adsorption and desorption of end-constrained chains (e.g. by crosslinks or entanglements) from a polymer melt onto a solid substrate. This approach is tested on a polyethylene/graphite system, where the whole methodology is parametrized by atomistically detailed molecular simulations. For short-chain melts, which can still be addressed by molecular dynamics simulations with reasonable computational resources, the self-consistent field approach gives predictions of the adsorption and desorption rate constants which are gratifyingly close to molecular dynamics estimates.