Molecular simulation of thermosetting polymer hardening: reactive events enabled by controlled topology transfer

TL;DR

This paper introduces a combined QM/MM simulation approach with Monte Carlo methods to model chemical reactions during thermosetting polymer hardening, validated by experimental DSC data and property measurements.

Contribution

It presents a novel integrated simulation framework for accurately modeling complex chemical reactions in thermosetting polymers, bridging quantum mechanics and molecular mechanics.

Findings

Good agreement with experimental DSC data

Accurate prediction of heat of formation and mechanical properties

Effective modeling of epoxy curing process

Abstract

We present a quantum mechanical / molecular mechanics (QM/MM) to tackle chemical reactions with substantial molecular reorganization. For this, molecular dynamics simulations with smoothly switched interaction models are used to suggest suitable product states, whilst a Monte Carlo algorithm is employed to assess the reaction likeliness subject to energetic feasibility. As a demonstrator, we study the cross-linking of bisphenol F diglycidyl ether (BFDGE) and 4,6-diethyl-2-methylbenzene-1,3-diamine (DETDA). The modeling of epoxy curing was supplemented by Differential Scanning Calorimetry (DSC) measurements, which confirms the degrees of cross-linking as a function of curing temperature. Likewise, the heat of formation and the mechanical properties of the resulting thermosetting polymer are found to be in good agreement with previous experiments.