Polyethylene based on molecular weight design for eco‐friendly asphalt

Abstract

Polyethylene (PE) is widely used as a modifier for asphalt due to its low cost. However, PE increases the high‐temperature viscosity of asphalt, leading to higher construction temperatures and harmful emissions. In this study, PE‐modified asphalt with good road performance, energy saving and emission reduction was synthesized by adjusting the molecular weight (Mw) of PE. By studying the effect of PE with different Mw on the viscosity of asphalt, the Mw of PE that can reduce the high‐temperature viscosity of asphalt was concluded and the target product PE‐4 was synthesized. PE reduces the high‐temperature viscosity of asphalt when its Mw is less than the critical molecular weight (Mc) for molecular chain entanglement in the molten state. PE‐4 successfully reduced the high‐temperature viscosity of matrix asphalt. The pavement performance of PE‐4 modified asphalt was characterized. The results showed that PE‐4 reduced the penetration of asphalt, and improved its softening point, ductility, and rutting resistance. PE‐4 modified asphalt is an eco‐friendly asphalt with good road performance. The above data proved that PE with Mw less than Mc makes PE a promising asphalt modifier, which is beneficial to the green utilization of PE.

Microscopic Properties of Asphalt and Polyethylene at an Extraordinary High Dosage through Molecular Dynamics Simulation

“…To address this issue, researchers have employed chain group modification methods, such as NH 2 -terminated PE [27], epoxyterminated PE [28], or maleic anhydride grafted PE [29,30], to improve the storage stability of PEA. Additionally, the modification of polymer molecular architecture has been explored to promote the compatibility of PEA to some extent, including the molecular weight (MW) [31][32][33] and branch distribution [34,35] from experimental work. Despite numerous experimental efforts to modify PE, phase segregation and storage stability problems still limit the large-scale loading of PE in modified asphalt materials.…”