An Investigation on the Compatibility of Epoxy Resin and Asphalt Based on Molecular Simulation

Abstract

Epoxy resin and asphalt compatibility have a significant impact on the material qualities of epoxy-modified asphalt. At present, there is a shortage of the study on the compatibility mechanism from the standpoint of nano. This paper evaluated the influence of temperature on the compatibility of epoxy resin (ER) and asphalt using the molecular dynamics (MD) simulation approach to explore the compatibility between ER and asphalt in greater detail. First, a twelve-component molecular model of asphalt was built, as well as a model of the system following cross-linking of epoxy resin and curing agent. And model optimization and model validation were performed. Secondly, the model of ER and asphalt co-blended system was constructed by combining the optimized model with the Amorphous Cell module. Then, MD simulations were done at various temperatures to derive the solubility parameters and intermolecular interaction energy of the mixed system for each system. Finally, the compatibility of ER with asphalt at different temperatures was analyzed based on the calculation results. It was found that the compatibility of ER and asphalt was temperature dependent. As the temperature increased, the solubility parameters of ER and asphalt decreased, and the difference in solubility parameters Δδ between them took the minimum value at 170 °C. As the temperature rises, so does the total potential energy in each system, and the intermolecular interaction energy of ER and asphalt mixed system achieves the maximum value at 170 °C. Currently, the structure of ER and asphalt mixed system is the most stable, and the compatibility between the two is the best.