Effect of SBS/SBR/component molecular compatibility on anti-aging properties for asphalt binder

To explain the effect of SBS/SBR/component molecular compatibility on anti-aging properties for asphalt binder, the micro-aging behavior of SBS/SBR composite modified asphalt binder was studied by molecular simulation, scanning electron microscopy (SEM) and infrared spectroscopy (IR). First, the micro-models of SBS molecule, SBR molecule and component molecule (asphaltene, resin, saturation, aromatic) were established, and the molecule number was determined by component test. Additionally, the characteristics of micro-model were analyzed, and the change characteristics of molecular compatibility for unaged asphalt binder and aged asphalt binder were obtained. Lastly, the rationality of molecular compatibility simulation results of SBS/SBR/component was demonstrated by SEM and IR tests, respectively. The results show that there is a close relationship between SBS/SBR/component molecular compatibility and asphalt binder anti-aging performance. The change of molecular space structure leads to the increase of asphalt binders density and the decrease of intermolecular distance. The study revealed the anti-aging properties of asphalt binder from the aspect of SBS/SBR/component molecular compatibility, which provided a theoretical foundation for the improvement of its aging resistance.