Modification of Epoxy Asphalt by Low-Doping PE-GMA and PE-MAH

Low-density polyethylene grafted glycidyl methacrylate (PE-GMA) and low-density polyethylene maleic anhydride (PE-MAH) are low-cost commercialized polymeric materials. Because of their low viscosity, molecular flexibility, solubility parameters, and polarity similar to asphalt or epoxy resins, PE-GMA and PE-MAH are added to epoxy asphalt (EA) to improve the compatibility and toughness of EA. The microstructure, viscosity, thermal stability, dynamic mechanical behavior, and mechanical properties of PE-GMA and PE-MAH modified EA were investigated. Smaller and more uniformly distributed asphalt particles were formed in mixes with lower PE-GMA or PE-MAH content. The polymer dispersity index of the modified EA is 1.1-1.4 lower than that of the pure EA, and compatibility is significantly improved. The reason is that PE-GMA and PE-MAH are polyethylene with polar functional groups, and their molecular structure includes both polar functional groups and nonpolar polyethylene chains, improving the compatibility between polar epoxy resin and nonpolar asphalt in EA. In addition, the incorporation of PE-GMA or PE-MAH effectively improves the low-temperature toughness of EA. It also has high damping performance and tan delta, improved the durability and comfort of EA pavement.