Study on Physical Properties, Rheological Properties, and Self-Healing Properties of Epoxy Resin Modified Asphalt

To investigate the effects of epoxy resin at low content on the physical properties, rheological properties, and self-healing properties of asphalt, epoxy asphalts with epoxy resin contents of 2%, 5%, 10%, and 20% were prepared. The distribution of epoxy asphalt (EA) in epoxy resin (ER) was quantitatively studied by fluorescence microscopy (FM) to investigate the feasibility of the preparation process. The glass transition temperature of epoxy asphalt was quantitatively analyzed by the differential thermal analyzer (DSC). The physical properties of epoxy asphalt were characterized by penetration test, ductility test, and softening point test. The rheological properties of epoxy asphalt were analyzed by the dynamic shear rheometer (DSR) to evaluate the self-healing properties of epoxy asphalt. The results show that the epoxy resin could be uniformly distributed in the asphalt, as verified by fluorescence microscopy (FM). With the increase in epoxy resin content, the glass transition temperature of epoxy asphalt gradually decreases, and the epoxy asphalt with 20% content shows the lowest glass transition temperature. At the same time, epoxy resin gives asphalt a higher modulus and high temperature performance, and the penetration and softening point of epoxy asphalt has also been greatly improved. On the contrary, the three-dimensional cross-linked grid structure, which is formed by epoxy resin and curing agent, reduces the rheological properties of epoxy asphalt and increases the elastic components of epoxy asphalt. Although the maltenes diagram still exhibits typical viscoelastic characteristic, the flow behavior index and flow activation energy of epoxy asphalt decreased.