(594h) What Makes Paint Stick? Insights from Computer Simulations of Epoxy Resin Binding on Iron Oxide / Oxide-Hydroxide Surfaces
AIChE Annual Meeting
Tuesday, November 16, 2021 - 8:50am to 9:15am
Here we perform atomistic molecular dynamics simulations to investigate the binding of common epoxy resin components to different iron oxide/ oxide-hydroxide surfaces. We calculate the binding energy, a measure of the energy difference between the bound adsorbate and the adsorbate at infinite distance from the surface, alongside free energy calculations which are computationally more demanding but provide valuable insight into the underlying free energy landscape that drives adsorption.
In epoxy resin applications the composition of the solid substrate is highly varied, with pre-treatments and production processes leading to a non-uniform surface chemistry and roughness. To reflect this, we investigate three different iron oxide/ oxide-hydroxide surfaces; hematite (Fe2O3) and magnetite (Fe3O4) and goethite (FeOOH) and consider different surface hydroxylation levels. We compare our findings with experimental results and find that the binding of epoxy components to each surface is quantitatively different. From these results, we suggest reasons for this trend based on the surface termination and gain fundamental understanding on how epoxy resins bind to metal substrates.