Self-healing recyclable bio-based magnetic composites with boronic ester vitrimer matrix

The ongoing energy crisis and increasing consumption of fossil-based feedstock have raised the awareness of researchers about the need to develop sustainable alternatives for conventional plastic materials. A great potential is attributed to vitrimers, a newly emerging class of polymer materials that, despite being covalently crosslinked, can be easily repaired, reprocessed, or recycled with minimal environmental impact. Such properties are achieved due to dynamic cross-links that enable the reversible reactions within their network structure. Here, we report on the development of a novel bio-based magnetic composite by adopting the catalyst-free vitrimer as a host matrix for embedding the magnetic micro-filler. The employed matrix uses a recent generation of the exchange reactions ensured by boronic ester metathesis, following the principles of "green" chemistry. The final composite is endowed with various useful, programmable, and unique features, such as hardening in magnetic fields, electromagnetic shielding capability, and directional self-healing capability, while also being reprocessable multiple times and easily recyclable.