Preparation and Properties of High-Viscosity Asphalt Using WTR, Terpene Resin, and APAO

Abstract In this research, a novel high-viscosity asphalt (HVA) is developed using renewable modifiers to reduce its environmental impact and cost over traditional polymer modifiers such as styrene-butadiene-styrene and Tafpack super. Waste tire rubber (WTR) was utilized to increase the viscosity and improve the rheological properties of asphalt matrix at a relatively low cost. Amorphous poly alpha olefin (APAO) and terpene resin (TR) were used in the study to promote the effect of WTR and reduce the reaction temperature of the modification process. The rheological properties of asphalt matrix, WTR rubber-modified asphalt (RMA), and HVA were evaluated by dynamic shear rheometer, and the internal microstructure was observed by fluorescence microscopy and Fourier transform infrared spectroscopy to evaluate the compatibility of the prepared asphalts. The reaction temperature was reduced by 20°C–30°C. The optimum dosage of WTR, APAO, and TR was determined as 20 percent asphalt by weight (wt%), 5 wt%, and 3 wt%, respectively. Experimental outcomes indicated that the optimum modifiers appreciably increased the viscosity by 2.5 times (higher than 20,000 Pa·s at 60°C) and increased the ductility and softening point of RMA by approximately 50 % and 10 %, respectively. The HVA exhibited greater resistance to permanent deformation at high temperatures and to cracks at low temperatures. Because of the chemical and physical reaction between the asphalt phase and WTR, the addition of APAO and TR promoted the swelling of rubber powder and improved the uniformity of the system.