Comparative Analysis of Rheological Properties and Modification Mechanism of SBS-Graphene Composite Modified Binder

SBS (styrene-butadiene-styrene block copolymer) has been widely used in pavement industry as an asphalt modifier. Nanomaterials can further enhance the performance of SBS modified asphalt. However, rare studies investigate the feasibility of using graphene as a performance enhancer of SBS modified asphalt. To fill this gap, comprehensive experimental tests including chemical and mechanical test were carried out on SBS-graphene modified asphalt and SEBS (styrene-ethylene-butylene-styrene block copolymer, which is a hydrogenated polymer of SBS) modified asphalt. Graphene with different dimensions and contents was taken into consideration in this study. Based on the experimental work, it can be concluded that graphene improves the mid-temperature performance of SBS modified asphalt. Compared with two-dimensional graphene, three-dimensional graphene has a greater advantage and the enhancement effect increases with the increase of its dosage. In addition, the cross-linked structure of SBS-graphene composite improves the distribution of SBS in asphalt, which improves the overall performance of SBS modified asphalt.