Pathways towards a circular economy for thermoset nanocomposites

The growing adoption of thermoset nanocomposites across industries has raised concerns about their environmental impact and end-of-life management. These advanced materials, which combine nanoscale fillers with permanently crosslinked matrices, pose unique recycling challenges due to their inherent durability and resistance to conventional mechanical recycling methods. This perspective examines prospective approaches for achieving circularity in thermoset nanocomposites, focusing on two main strategies: reprocessing and nanofiller recovery. We analyse recent developments in the use of covalently adaptable networks (CANs) as reprocessable matrices for nanocomposites. We also evaluate physical, thermal, and chemical methods for recovering valuable nanofillers from thermoset nanocomposite waste. While significant progress has been made in developing recyclable matrices and recovery techniques for conventional composites, additional research is needed to address challenges specific to nanomaterials, including preventing nanomaterial agglomeration and surface chemistry preservation. Moving forward, tailored approaches considering the unique characteristics of different nanofiller types will be crucial for establishing effective recycling protocols and advancing towards a circular economy for these high-performance materials.