Effects of Physio-Chemical Factors on Asphalt Aging Behavior

Based on an accelerated asphalt-aging test in the laboratory, the authors evaluated the physical and chemical properties of asphalt at different aging times and temperatures for this paper. They evaluated the properties of the asphalt binder, such as saturates, aromatics, resins, asphaltenes, penetration, softening point, and molecular distribution of the asphalt, by using experimental results from the accelerated asphalt-aging tests. They employed gel permeation chromatography (GPC), Fourier transforms infrared spectroscopy, asphalt constituents fraction analysis, and rheological test techniques to analyze the effects of asphalt from different crude oil sources on antiaging performance. They used asphalt-aging tests to determine the relevant kinetic parameters needed in the aging kinetics equation. They found that the asphalt-aging reaction perfectly fits to the first order kinetics equation, and during the asphalt-aging process, the asphalt had a higher activation energy and a lower reaction rate coefficient. Moreover, the molecular weight (MW) of asphalt increased, whereas the dispersity decreased. The asphalt-aging process was divided into two stages: one stage is from aliphatic sulfide to sulfoxide and the other stage was from benzylic carbon to carbonyl. The aging resistance of asphalt was influenced by the asphalt fraction, wax content, and molecular weight.