C9 Petroleum Resin and Polyethylene-Based High-Viscosity Modified Asphalt Binder Proportioning Optimization and Performance Study

This study, based on 90# matrix asphalt binder, investigates the use of SBS, C9 petroleum resin, and polyethylene (PE) as modifiers to prepare high-viscosity modified asphalt binders. Using the uniform design method, the modifier proportions were optimized to meet engineering requirements for high viscosity. The effects of modifier dosages on asphalt binder properties, including penetration, ductility, softening point, and dynamic viscosity, were systematically analyzed, and a multivariate nonlinear regression model was constructed to determine the optimal proportioning. Subsequently, the aging resistance and high-temperature performance of the modified asphalt binders were evaluated through short-term aging tests and rheological property tests. The results show that SBS and PE have a significant positive impact on penetration and softening point, while C9 petroleum resin mainly enhances ductility. The synergistic effect of SBS and PE significantly improves dynamic viscosity. Under the optimal proportioning (SBS 7.5%, C9 petroleum resin 6.0%, PE 5.0%), the high-viscosity modified asphalt binders meet technical standards for key performance indicators. The short-term aging test reveals an elastic recovery ratio exceeding 95%. Rheological performance testing indicates that the modified asphalt binders exhibit excellent rutting resistance and temperature adaptability under high-temperature conditions.