On Investigating the Thermomechanical Properties of Cross-linked Epoxy Via Molecular Dynamics Analysis

ABSTRACT

In this work, we demonstrate the feasibility of a computational approach based on first principles for estimating various thermomechanical quantities of a cross-linked epoxy resin. In particular, this work is focused on determining estimated values of the variation in glass transition temperature, coefficient of thermal expansion, volume shrinkage due to curing, Young’s modulus, Poisson’s ratio, yield strength, and viscosity as a function of temperature and degree of curing via molecular dynamics simulations. In most cases it has been demonstrated that the values predicted by the proposed approach are in good agreement with the respective experimentally measured values. In addition, the validity of the proposed models describing the dependence of the thermomechanical quantities on temperature and curing degree is examined. Throughout this study, we demonstrate that the molecular dynamics–based computational predictive framework can serve as an excellent infrastructure that can enable numerical prediction of materials properties and thereby can reduce the costs of associated with physical experimentation. In addition, we demonstrate that insightful information can be generated at the molecular and microscopic scales that is not easily extractable from experiments.

KEYWORDS:

• Full atomistic molecular dynamics
• cross-linking
• thermomechanical properties
• epoxy resin

Funding

This work utilized the Janus supercomputer, which is supported by the National Science Foundation (award number CNS-0821794) and the University of Colorado Boulder. The Janus supercomputer is a joint effort of the University of Colorado Boulder, the University of Colorado Denver, and the National Center for Atmospheric Research. The second author acknowledges support by the Office of Naval Research through the core funding by the Naval Research Laboratory.