Enhancing fiber-reinforced asphalt binders via graphene oxide grafting: A novel interfacial modulation strategy

Abstract

This study reports a novel interfacial enhancement strategy for fiber-reinforced asphalt binders. The graphene oxide (GO) nanosheets were used and grafted onto polyester (PET) and polyacrylonitrile (PAN) fibers in order to enhance the performance of modified asphalt binders. Prior to this, ultraviolet ozone (UVO) treatment was primarily adopted for activating the inert surface of fibers. Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Scanning electron microscope (SEM) confirmed that GO-modified fibers were successfully prepared via surface modification. For the rheological properties determined by dynamic shear rheometer (DSR), the asphalt binders with GO-modified fibers exhibit improved high-temperature rutting resistance, better creep and recovery characteristics and increased anti-fatigue properties. Remarkably, it demonstrates that the recovery (R) value of GO-PAN modified asphalt binder is increased by 21.9 %, and the non-recoverable compliance (Jnr) value of GO-PET modified asphalt binder has been reduced by 31.9 % compared to that reinforced with the unmodified fiber in multiple stress creep recovery (MSCR) tests. These enhancements are mainly attributed to the increased roughness and modulus of the GO-grafted fibers, which promote effective stress transfer at the fiber-asphalt interfaces. Results from the atomic force microscope (AFM) indicate that the Young’s modulus of GO-PET and GO-PAN is 94.2 % and 260.0 % higher than that of PET and PAN, respectively. This research not only provides a simple and cost-effective method for improving the rheological performance, but also elucidates the enhancement mechanism of interfacial behavior in fiber-reinforced asphalt binders.