Study on the low-temperature performance of chemically cross-linked polyethylene composite modified asphalt binder

The great disadvantage of polyethylene modified asphalt in terms of low-temperature performance has led to limitations in its large-scale application. The aim of this study was to investigate whether peroxides and silane coupling agents can significantly improve the low-temperature performance of modified asphalt through chemical cross-linking. Therefore, nine experimental groups were designed through orthogonal experiments, and the low-temperature properties of matrix asphalt, control asphalt, and nine modified asphalt groups were evaluated by using a bending beam rheometer, and microscopic analyses were carried out using FM, SEM, and FTIR tests. The experimental results showed that the 5 degrees C ductility increased to a maximum of 136.3 % and 166.2 % compared to the matrix asphalt and control asphalt, and the cross-linking between the polymer and the asphalt was enhanced microscopically. Chemical cross-linking of asphalt and polymer using peroxide and silane coupling agent provides a feasible method to expand the application of polymer in pavement engineering.