Research Information System
Construction and Building Materials, vol.494, 2025 (SCI-Expanded)
The stiffness and workability of neat asphalt binders are adversely affected by a high asphaltene content. Furthermore, this relationship becomes more complicated when these binders are modified with polymers. Therefore, in this study, an asphaltene dispersant (AD) was developed and used in styrene-butadiene-styrene (SBS)-modified asphalt binders with high asphaltene content to address the problems in consistency and workability due to the combined effect of high-asphaltene binder and polymers. When preparing the modified asphalt binders, the developed AD was used at the rates of 1 % and 2 %, and SBS was utilized at the rates of 3.5 %, 4.5 %, and 5.5 %, both by weight of asphalt binder. The effect of AD on the chemistry of binders was analyzed with SARA fractions, Fourier transform infrared spectroscopy (FTIR), and fluorescence microscopy (FM). Moreover, conventional and rheological tests, multiple stress creep recovery (MSCR), and linear amplitude sweep (LAS) were performed to evaluate the performance of the AD-SBS modified binders. From the SARA analysis, it can be concluded that AD decreased the viscosity and stiffness of binder as a result of a relative reduction in asphaltene content. Hence, the AD-SBS modified binders had lower viscosity and improved workability than the SBS modified binders. FM analysis revealed that AD increased the compatibility and dispersion of the SBS polymer, resulting in superior three-dimensional crosslinking within the asphalt binder matrix throughout the aging compared to SBS-modified binders. Eventually, this study suggests a guide to optimize the AD content to improve workability, fatigue, and low-temperature performances while slightly jeopardizing the rutting performance of the SBS-modified binders.