Bio-based polymer modified asphalt: Current status and challenges

Polymers have been widely used in asphalt materials. Currently, many scholars have used bio-based materials instead of petroleum-based materials to synthesize bio-based polymer-modified asphalt. This paper reviews the bio-based materials extensively employed in modified asphalt in recent years, such as vegetable oils, plant phenols, lignin, rosin, and itaconic acid. The material composition and modification mechanisms of bio-based thermosetting resin modified asphalt, bio-based elastomer modified asphalt, bio-based rubber modified asphalt, and bio-based composite modified asphalt are outlined. The performance advantages of different thermosetting resin modified asphalts are summarized. The life cycle assessment of bio-based polymer-modified asphalt and traditional polymer-modified asphalt is studied. Finally, the recycling and regeneration performance of bio-based polymer-modified asphalt to achieve green and environmental protection in multiple links are investigated. The results show that bio-based modified asphalt has better environmental performance and road performance, and can be widely used in practical engineering. This paper provides a reference for the research on bio-based polymer-modified asphalt. The existing issues and further research orientations of bio-based polymer-modified asphalt are envisioned.