Improving the compatibility of cold-mixed epoxy asphalt based on the epoxidized soybean oil

Abstract Cold-mixed epoxy asphalt (CEA) has been used for paving steel bridges and high-grade roads because of its properties superiority and environmental protection. In order to obtain CEA with excellent performance, it is a significant mean to improve the compatibility between asphalt and epoxy resin (ER) by introducing epoxidized soybean oil (ESO). The viscosity and glass transition temperature ( T g ) decrease, and the asphalt dispersed more uniformly in the ER with increasing ESO concentration. Based on the dynamic mechanical analysis, the CEA-ESO30 shows only one T g and excellent compatibility between asphalt and ER. The elongation at break and storage modulus of CEA-ESO was higher than CEA, indicating that the flexible ESO molecular chain in the curing networks might improve the stiffness of CEA-ESO. The FTIR spectra exhibited that the ESO reacted with the curing agent to form 3D networks with ER, which may result in good compatibility between asphalt and ER.