Synthesis Strategy and Fundamental Validation of Recyclable Epoxy Asphalt

Abstract:

Epoxy asphalt, characterized by its covalently crosslink three-dimensional micro-structure, functions as a key binding agent in the construction of orthotropic steel deck systems for long-span bridges. As modern transportation infrastructure advances, the utilization of epoxy asphalt in roadway construction has significantly increased to meet the rising demands of growing traffic volumes. Consequently, the application of epoxy asphalt has progressively expanded; however, its recyclability remains a substantial technical challenge. Further foundational research is essential to develop recyclable epoxy asphalt that adheres to the principles of sustainability.
The recycling of epoxy asphalt poses significant challenges due to its inherently limited regenerative capacity, which results from the formation of irreversible covalent crosslinks during synthesis. In cases of premature bridge deck pavement failure or when roadways require repairs post-design life, aged epoxy asphalt mixtures are often discarded in landfills, which means that the current use of epoxy asphalt is not consistent with the concept of sustainability.
To address this critical challenge, recyclable epoxy asphalt has been designed based on the reversibility of dynamic covalent bonds. The synthesis strategy and basic validation of recyclable epoxy asphalt are therefore implemented in this work. Based on the selection of reversible covalent bond-forming reactions, specifically the Diels–Alder reaction, a design scheme for recyclable epoxy asphalt is first proposed. Then 13 distinct compositions varying two parameters and evaluating three mechanical properties are devised to determine the optimal material formulation for recyclable epoxy asphalt. Following the aging and regeneration processes, the study examines the chemical composition and rheological properties of recyclable epoxy asphalt before and after regeneration. The preparation-aging-regeneration cycle underscores the practicality of recyclable epoxy asphalt, demonstrating substantial environmental benefits and promising future applications.

Short bio:

Hello everyone! I started my PhD in September 2020 at Harbin Institute of Technology. Since June 2024, I have been working under the supervision of Laurent Brochard. My research focuses on asphalt pavement engineering, with a particular emphasis on the design principles and key preparation technologies of recyclable epoxy asphalt based on dynamic covalent bonding.