▎ 摘　　要

In order to improve the high temperature rutting resistance ability and stability of styrene-butadiene-styrene (SBS) modified asphalt, microwave heating emulsion polymerization strategy was used to prepare polymethyl methacrylate (PMMA) and graphene nanoparticles (GNPs) composite (PMMA-GNPs) which was used to prepare PMMA-GNPs/SBS modified asphalt. Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and thermogravimetric analysis characterizations showed that PMMA-GNPs particles were successfully prepared having a weight ratio of GNPs: PMMA of 1:9. Microwave heating reduced the reaction time from 5 h to 30 min compared to conventional oil bath heating. Dynamic shear rheological test and multi-stress creep recovery test confirmed that 0.06% PMMA-GNPs/SBS modified asphalt (0.06% PMMA-GNPs of the mass of base asphalt) exhibited an increase of 14.2% in elastic modulus (G'), while rutting resistance was enhanced and sensitivity to stress changes was reduced as compared to those of 5% SBS modified asphalt. Fluorescence microscopy analysis and phase separation test revealed that an appropriate amount of PMMA-GNPs can be uniformly dispersed in SBS modified asphalt and enhance the mutual interaction of SBS with base asphalt. Based on the results of mechanical tests and characterizations, a suitable modification mechanism of PMMA-GNPs particles in the original SBS modified asphalt was described in detail. This study proposes a simple, cost effective and fast strategy for the preparation of PMMA-GNPs incorporated SBS modified asphalt and hence can be envisioned of great promise in construction and highway industries.