A transparent, room-temperature self-healing, and flame-retardant peach gum-based vitrimer enabled by boronic ester bonds for sustainable materials

Recyclable bio-based vitrimers present a promising pathway to mitigate environmental pollution and diminish reliance on petroleum resources. However, integrating multiple functionalities, including flame retardancy, room-temperature self-healing, antibacterial activity, antioxidant performance, and closed-loop recyclability, into a single vitrimer system via a straightforward method remains a considerable challenge. Herein, we address this challenge by developing multifunctional bio-based vitrimers derived from natural peach gum polysaccharide (PGB) through direct curing with 1,4-phenylenebisboronic acid. The resulting cross-linked network exhibits excellent room-temperature self-healing capability, achieving over 94% healing efficiency within 180 min, attributable to the dynamic boronic ester bonds. Furthermore, the PGB vitrimers demonstrate outstanding flame retardancy, achieving a limiting oxygen index (LOI) of 33.8% and a UL-94 V-0 rating. They also possess significant antioxidant activity (>85% DPPH radical scavenging rate) and exhibit strong antibacterial efficacy against S. aureus , with an average inhibition zone diameter of 15.3 mm. Owing to their multifunctionality, sustainability, and straightforward preparation, these peach gum-derived vitrimers hold great potential for advanced applications in coatings, packaging, and soft electronics.