Physical, High-Temperature Rheological, and Aging Behaviors of Nano Antimony-Doped Tin Oxide–Modified Asphalt Binder

The ultraviolet shielding and solar energy absorption characteristics of nano antimony-doped tin oxide (Nano-ATO) make it helpful to improve the performance and service life of pavement caused by asphalt aging. In this study, nano-ATO asphalt was successfully prepared. By measuring its properties before and after short-term aging and ultraviolet aging, seven aging indexes were introduced to verify the positive influence of nano-ATO on the aging resistance of asphalt. Finally, the mixture was prepared to further verify the effect of nano-ATO. The results articulate that nano-ATO significantly improves the high-temperature performance indicators of asphalt, and the comprehensive performance of 5% nano-ATO asphalt is the best. The aging index of nano-ATO asphalt is closer to 100% or 0, which means that nano-ATO can enhance the thermal-oxidative and photo-oxidative aging resistance of asphalt. Nano-ATO can be uniformly dispersed in asphalt to form a physical barrier network, which can prevent or slow down the volatilization of light components, inhibit the oxidation reaction process, and reduce the damage to the molecular chains of asphalt caused by ultraviolet rays. The dynamic stability and immersion residual stability of the 5% nano-ATO asphalt mixture are as high as 5,118 times/mm and 93%, respectively, and the indicators only decrease by 8.6%–26% after two types of aging. This indicates that nano-ATO asphalt can optimize pavement performance and extend the service life of asphalt pavements. Most importantly, nano-ATO asphalt is more suitable for areas exposed to strong ultraviolet rays and high temperatures.