Analysis of OMMT strengthened UV aging-resistance of Sasobit/SBS modified asphalt: Its preparation, characterization and mechanism

To promote the application of warm mix asphalt (WMA) technology in strong UV areas, warm mix SBS modified asphalt binders with better UV aging resistance were developed in this study. The conventional physical properties, viscosity-temperature characteristics, rheological properties and storage stability were carried out to analyze the performance of the prepared modified asphalt containing Sasobit and OMMT. Then, TOPSIS method was selected for multi-index optimization to optimize the dosage of OMMT and Sasobit. Subsequently, the warm mix effect, high temperature property and aging resistance of the developed modified asphalt were further evaluated. Finally, the modification mechanism was characterized with FTIR, XRD and FM. Test results show that, Sasobit can significantly improve the construction workability of asphalt, and OMMT can enhance the storage stability and UV-aging resistance. In addition, the two modifiers can both improve the high temperature property of SBS modified asphalt. Based on the multi-index optimization results, it is recommended that the optimal dosage of Sasobit and OMMT is 3% and 2%, respectively. And microstructure characterization test results reveal that the asphalt chains and polymer molecules have been successfully intercalated into the layers of OMMT molecules, and further the exfoliated structure has been formed in the composite asphalt blend, thus improving its road performance. From the above results, it can be concluded that both additives play their own advantages at their optimum dosages.