Effect of Composite Light Stabilizer on the Anti-Ultraviolet Aging Property of Matrix Asphalt

Abstract

Ultraviolet (UV) radiation causes asphalt aging and thus influences its performance. In this research, a composite light stabilizer was prepared to increase the light stability of matrix asphalt. Benzotriazole UV absorber (UV928), a hindered amine radical scavenger (UV4050), and a light screening agent [layered double hydroxide (LDH)] were selected as light stabilizers to modify the matrix asphalt, and their properties were compared using a physical property test and rheological test before and after UV aging. UV aging and a rolling thin-film oven test (RTFOT) were applied to simulate laboratory accelerated aging. The one-component test results demonstrated that three kinds of light stabilizer improved the light stability of asphalt to some extent. However, before UV aging, the addition of light stabilizer caused a great loss of asphalt fluidity and reduced the low-temperature performance of asphalt, which influenced the original performance of matrix asphalt. Therefore, the composite light stabilizer was prepared to weaken the adverse effect of a single material on asphalt. The composite light stabilizer not only improved the fluidity and the low-temperature crack resistance of one-component modified asphalt. Moreover, from the perspective of high-temperature performance, it also reduced the adverse effects of UV radiation on asphalt. This implied that the composite light stabilizer not only reduced the adverse effects of one-component light stabilizer on asphalt but also ameliorated the light stability of matrix asphalt, and the three kinds of light stabilizer had a good synergistic effect.