Surface Modification of Recycled Polyester Fiber and Performance Evaluation of Its Asphalt Mastic and Mixture
Lei Xia, Dongwei Cao, Hongliang Zhang, Mingming Zhang, Lingyan Shan, Haiyan Zhang, Taiwei Wang
Abstract
The use of recycled polyester fiber (Re-PET) partially addresses the scarcity of non-renewable polyester (PET), but its thermal resistance in asphalt mixtures is relatively low. To enhance the reutilization and thermal resistance of Re-PET, it was modified through in situ growth grafting with tetrahedral nanoSiO2. A novel nanoSiO2 hybrid material (SiO2/Re-PET) was successfully prepared, and the effects of the surface modification on the morphology and thermal resistance of the Re-PET were investigated with the examination of its mechanism of modification. The results demonstrated an increase in the surface roughness and specific surface area of SiO2/Re-PET, as well as a higher melting point and structural stability compared to Re-PET. Subsequently, Re-PET and SiO2/Re-PET asphalt mastics under a filler–asphalt ratio of 1.0 were prepared, and their classical and rheological properties were investigated and compared. The results indicated an increase in the softening point and shear strength of SiO2/Re-PET asphalt mastic, as well as a significant improvement in its high-temperature performance. Furthermore, subsequent pavement performance tests revealed a significant improvement in the performance of SiO2/Re-PET asphalt mixtures compared to Re-PET asphalt mixtures. Consequently, the findings of this research promote the recycling of Re-PET, ultimately advocating for the sustainability of pavement construction.