Rheological and storage stability improvement of SBR modified asphalt binder using graphene

This study aimed to enhance the compatibility and rheological properties of styrene–butadiene rubber modified asphalt (SBRMA) through the incorporation of graphene (GR). 4% SBR-modified asphalt was blended with GR at varying contents of 0.5%, 1%, 1.5%, and 2%. Multiple stress creep recovery (MSCR), temperature sweep, linear amplitude sweep (LAS), bending beam rheometer (BBR), separation test, and Fourier transform infrared spectroscopy (FTIR) were used to investigate the rheological characteristics and modification mechanism of GR/SBR composite-modified asphalt. Results showed that storage stability, rutting resistance, elastic recovery, and fatigue performance of SBR-modified asphalt were enhanced by adding GR. However, the addition of GR detrimentally affected the low-temperature properties. FTIR spectroscopy indicated that the interaction between SBRMA and GR was mainly physical. A 1% GR is recommended for the best results when combined with SBR, improving compatibility, resistance to permanent deformation, ageing, and fatigue while having little negative impact on low-temperature performance.