Investigation on thermal aging stability of crosslinked styrene butadiene rubber modified asphalt binder

Abstract

This study investigated the thermal aging stability of crosslinked styrene–butadiene–rubber (SBR) modified asphalt binder at different aging extents. Crosslinked SBR modified asphalt was prepared by combining dithiodimorpholine (DTDM) with SBR modified asphalt. The rolling thin film oven test was utilised to simulate different thermal aging extents. The physical and rheological properties of asphalt binders were tested by using penetration, softening point, rotational viscometer and dynamic shear rheometer before and after aging. The chemical bond thermal stability of crosslinked system at different aging extents was investigated through using the Fourier Transform Infrared (FTIR). Results indicated that the crosslinked SBR modified asphalt had good aging resistance. Within 3 h aging, the chemical bond of crosslinked had good stability, the crosslinked SBR modified asphalt could maintain the high performance and mitigate the aging effect on asphalt binders. Besides, the carbonyl index with aging index had good correlation, and it could be used to reflect the aging extents of asphalt binder.