Study on the performance and mechanism of carbon nanomaterials incorporated SBS composite modified asphalt

Abstract

Based on the four-component separation technology of asphalt, the influence mechanism of carbon nanotubes (CNTs), graphene microsheets (GNPs) and graphene oxide (GO) in SBS-modified asphalt four-component was systematically analyzed by combining macroscopic properties and microscopic characteristics, as well as exploring the morphological distribution of SBS in asphalt four-component. According to the results of Fourier transform infrared spectroscopy and field emission scanning electron microscopy, the modification mechanism of asphalt by three types of carbon nanomaterials follows two pathways: chemical reaction and physical blending. The addition of CNTs, GNPs, and GO results in the destruction of long carbon chains of the saturated fraction in SBS-modified asphalt, and promotes the aggregation of SBS in the asphaltene, as well as its dense distribution and crosslinking in the oil fractions. The results of the fluorescence microscopy test and phase separation test showed that the dispersing effect of the three carbon nanomaterials could alleviate the aggregation phenomenon of SBS, improve the mutual integration between SBS and matrix asphalt, and promote the storage stability of SBS-modified asphalt. Therefore, based on the excellent mechanical properties of the three carbon nanomaterials and their promotion of filling and crosslinking of SBS in asphaltene, they have made significant contributions to the mechanical properties of carbon nanomaterials-composite SBS modified asphalt. This can also be demonstrated by DSR testing and conventional physical property testing. This study hopes to provide a viable analytical route for the use of nanomaterials in modulating the four-component structure and improving the properties of asphalt.