Preparation and Microscopic Characterization of Asphalt Modified by Ethylene Metal-free Phthalocyanine-dispersed Graphene

Graphene-modified asphalt (GMA) for road application was prepared via using metal-free phthalocyanine-dispersed to modify an SK-70# base asphalt with graphene. The preparation parameters are as follows: the content of graphene is 0.26% based on the mass percentage of absolute ethanol, the content of nonmetal phthalocyanine is 190% based on the mass percentage of graphene, and then the GMA is prepared via unique high-speed shearing with continuing to ventilate nitrogen, which can prevent the aging of modified asphalt in the high-speed shearing process, and effectively evaluate the modifier. The penetration, softening point, force ductility, and fracture energy of GMA were significantly improved based on the base asphalt. Thus, the incorporation of graphene could enhance the base asphalt’s high- and low- temperature stability. The modification mechanism was researched via metallographic microscopy, computed tomography (CT), Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM). Adsorption and physical dispersion of the asphaltenes and resins in the phthalocyanine-graphene system were confirmed.