Metal-Free Synthesis of Biobased Polyisoxazolines toward Sustainable Circular Materials

In this study, we report the synthesis of sustainablepolyisoxazolinesusing a vanillin-derived bifunctional nitrile oxide monomer in metal-freenitrile oxide cycloaddition polymerization under mild conditions.The bioderived polyisoxazolines have high biomass contents in highyields with tunable glass transition temperatures. The furan-containingpolyisoxazoline could also be cross-linked by using dynamically exchangeablebonds to yield a circular material that can be easily reprocessedfor multiple cycles after use. The material's circularity wasdemonstrated by encapsulating a thermoelectric generator, which couldbe recycled easily to obtain the original generator and polymer fordevice refabrication, showing potential in reducing electronic wastein green electronic applications.