Microscopic Mechanism of Direct-Input Waste Plastic Modified Asphalt

Abstract

The continuous pollution of waste plastics to the ecological environment has attracted global attention. Using waste plastics in road construction can save energy, reduce pollution, and improve the high-temperature performance of asphalt mixtures. It will be the development trend of road materials in the future, but there have been few in-depth studies and evaluations on it. This study evaluated the microscopic characteristics of waste plastic modified asphalt. After the investigation and screening, this study used low-density polyethylene (LDPE) recycled materials in waste plastics as the main research object and used twin-screw extruders and instant dispersants to directly modify them and optimize the modification process parameters. In this way, a direct throw-in type of waste plastic asphalt modifier was prepared. Through fluorescence microscopy, infrared spectroscopy, scanning electron microscopy, gel chromatography, X-ray diffraction methods (XRD), and other technical means, the modification mechanism of direct-input waste plastic modified asphalt was analyzed. The test results show that the direct-input waste plastic modifier can achieve micron-level dispersion in the asphalt under the action of the instant dispersant, which can significantly improve the high-temperature performance of the asphalt mixture.