Molecular dynamics simulation of crosslinked epoxy resins: Curing and mechanical properties

Abstract

We performed molecular dynamics (MD) simulation that includes multidisciplinary characteristics from synthesis to mechanical properties of epoxy resin. First, to reproduce the actual chemical reaction between matrix and curing agents, we conducted curing simulation wherein the activation energy and heat of formation are considered for the chemical reaction. Subsequently, we performed MD simulations using cross-linked structure obtained from curing simulation to derive density and Young's modulus. Results indicated that crosslinked structures involving both activation energy and heat of formation could reproduce experiment results that are evaluated using differential scanning calorimetry (DSC) measurements and mechanical tests. The simulated results imply that electrostatic interaction plays an important role in Young's modulus. The density of the hydrogen bond between the oxygen of the hydroxyl group and the hydrogen atom is a key factor for the difference in Young's modulus for each base resin. These findings confirm that MD simulation is a potential alternative to experiments for the appropriate material selection of epoxy resin.

Synthesis and Characterization of Epoxy Thermosetting Polymers from Glycidylated Organosolv Lignin and Bisphenol A

“…This is within expectations for DGEBA‐based epoxy thermosetting polymers. In literature, values around 3 GPa are reported . 10% replacement of DGEBA by lignin led to a drop of E from 1.88 to 1.82 GPa.…”

Clustering Approach for Multidisciplinary Optimum Design of Cross‐Linked Polymer

“…We developed a new full‐atomic MD method for comprehensively predicting chemical and mechanical properties that addresses activation energy and heat of formation in chemical reaction, where these energies are evaluated by the molecular orbital (MO) method . As a result, curing characteristics and mechanical properties agree well with the experiment results . Therefore, even in a cross‐linked polymer system, the MD study may be an alternative to experimental trial and error for investigating multidisciplinary characteristics.…”

“…First, the cross‐linked structures of thermosetting resin are produced by chemical reaction between base resins and curing agents. For the curing reaction, we employed the Monte‐Carlo method, in which the criterion in reproducing the cross‐linked structure is a reaction probability ( P ) based on the Arrhenius equation where A is the acceleration factor (1 × 10 8 ), Δ G is the activation energy, k B is the Boltzmann constant, and T is the local temperature. The curing reactions generate the heat of formation.…”

Effect of amine functionalized MWCNT‐epoxy interfacial interaction on MWCNT dispersion and mechanical properties of epoxy‐amine composites

“…Epoxy‐amine systems are one of the most widely used matrix materials in fiber‐reinforced polymer composites because of their excellent mechanical, chemical stability and adhesive properties . Adding nano‐scale additives, such as carbon nanotubes (CNTs) , carbon nanofibers and graphene into the matrices can offer the possibility of further enhancing various performances in the resulting composites , matching the demand for light‐weight and high‐strength materials that are critical for next‐generation high performance composites , such as spacecraft subassembly, commercial aircrafts and electric cars.…”