Exploiting graphene oxide as a potential additive to improve the performance of cold-mixed epoxy asphalt binder

As a green material for high-performance paving, cold-mixed epoxy asphalt (CEA) should be improved in compatibility, mechanical performance, and thermal stability. This work is going to estimate the potential of graphene oxide (GO) as an additive for preparing GO/CEA composites with different GO content from 0 to 0.2 wt%. The influences of GO on the structure and performances of CEA were evaluated by Fourier transform-infrared spectrum, fluorescence microscopy, viscosity, thermogravimetric analysis, tensile test, and dynamic mechanical analysis. Results showed that the functional groups on GO reacted with CEA and improved the compatibility of epoxy resin and asphalt. The viscosity of the GO/CEA composites increased slightly and the pot life decreased significantly, with GO loading increasing. The cured GO/CEA composite with 0.1 wt% GO had the best heat resistance and showed a gentle thermal decomposition. GO improved the toughness of the cured CEA and had a certain weakening effect on its strength. The introduction of GO lowered the glass transition temperature of the cured CEA from 51.4 to 47.1 degrees C and decreased its storage modulus. The preliminary exploration of this study shows that the modification of GO for CEA is feasible, and it is expected to prolong the service life of CEA.