Research On The Ultraviolet Aging Of SBS

The thermo-oxidative aging and ultraviolet radiation aging will happen when SBS modified asphalt is exposed to high temperature and ultraviolet irradiation which reduce its the functionality and lifetime.The research about thermo-oxidative aging and ultraviolet radiation aging are very important for improving the usability performance of SBS modified asphalt. There has been a lot of studies about thermo-oxidative aging and ultraviolet radiation aging and most of them are focused on the whole system structures of SBS modified asphalt:In fact,the ingredients of SBS modified asphalt interfered each other during the process of thermo-oxidative aging and ultraviolet radiation aging,hence the knowledge of aging behaviors of SBS modified asphalt is limited.Therefore, in this article,a separation method of SBS modified asphalt is established and the ultraviolet radiation process is explored.With SBS modified asphalt as raw materials, the thin film oven aging test method was applied to simulate the short term aging of SBS modified asphalt mixture occurred in the process of storage, transportation, construction, and mixing; then the indoor and outdoor ultraviolet ardiation aging experiments of SBS modified asphalt carreid out by the ultraviolet radiation and natured light aging. The visual observation and fluorescence microscopy observation on SBS modified asphalt in different aging time in different ways are done.Finally, four components and SBS were separated,and the structure change of each component with aging time increasing is analyzed. The study provide a foundation for the more accurate of thermal-oxidative aging mechanism and ultraviolet radiation aging mechanism,which has significant meaning for the evaluation and prediction of photo-oxidation performance of SBS modified asphalt.Through the research, the conclusions are as follows:1.The SBS separation method is feasible,although there exists some loss of SBS,and SBS contains aromatics and resins.2.With the aging time increasing, the color of SBS modified asphalt changes from black to gray; and there is obvious shrinkage and wrinkles hardening increases. Under fluorescence microscopy SBS is found to be dispersed inside asphalt.3.The determination results of SBS modified asphalt aged for different time test,show that the aromatics content, saturates content and SBS content slightly drop, while the resins content, the asphaltenes content and Ic content slightly rise.4.The component of the SBS modified asphalt can be analyzed by four infrared and SBS, the most obvious change is the that increase of carbonyl and sulfoxide group content and decrease of PB’s characteristic peaks after ultraviolet light aging.