Investigation of epoxy-resin-modified asphalt binder

Epoxy asphalt (EA) binder has been used extensively for paving long-span bridges in many countries because it shows excellent heat resistance, is free from bleeding, has a low-temperature cracking resistance, and has aggregate scattering resistance. EA binders were prepared by the mixture of asphalt, epoxy resin, and a new curing agent (CR) with functional groups. The properties of the EA binder were characterized by their viscosity, tensile strength, elongation at break, compatibility, morphology, glass transition temperature (T-g), contact angle, and surface free energy. The curing process was analyzed. The results indicate that the curing temperature and asphalt content had significant effects on the properties of the EA binder. We observed that most of the strength was generated after the first 3h at 165 degrees C; this provided good workability for EA pavement construction. The CR with various functional groups improved the compatibility and morphology of the EA binder. The test results show that T-g of the EA binder decreased and the contact angles increased with increasing asphalt content. It is worth noting the contact angles between water and the EA binder were always greater than 90 degrees; this implied that the EA binder was hydrophobic and, hence, water repellent. The surface free energy and dispersion force increases with decreasing asphalt content. However, the polarity forces decreased with decreasing asphalt content. (c) 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43401.