Long afterglow epoxidized soybean oil polymer composites with reversible dynamic cross-linking for intelligent coating†

High-performance coatings with advanced functions such as long afterglow luminescence and self-healing have attracted great interest around the world, but the integration of these desirable multiple functions into a single composite system still remains a great challenge. Herein, an intelligent coating based on epoxidized soybean oil and modified long afterglow powders is presented for a self-healing intelligent coating. By constructing a dynamic hydrogen bonding network between natural polyphenols and epoxidized soybean oil, the obtained composites show desirable adhesive performances and self-healing ability: the shear strength of the obtained coating is able to reach 313.96 kPa while the self-healing efficiency was about 81.29% after a damage–healing process. Moreover, the introduction of SiO₂-modified SrAl₂O₄:Eu²⁺,Dy³⁺ powders endows the intelligent coating with long afterglow ability, which greatly benefits the visualized monitoring of small cracks. Meanwhile, the obtained bio-sourced composites could be degraded under anaerobic composting conditions within 5 days, and after degradation the long afterglow powders could be separated and recycled with almost consistent performance (luminescent intensity remains 95.19%) in contrast to the original powders. This study offers valuable examples and new insights for the high-value utilization of bio-based materials.