Upcycling of post-consumer polyolefin plastics to covalent adaptable networks via in situ continuous extrusion cross-linking

The huge amount of plastic waste is imperiling our daily life. Here, we designed a green and efficient large-scale one-pot method combining grafting and reversible cross-linking on a twin-screw extruder. Post-consumer plastic bags were upcycled to covalent adaptable networks (CANs) based on internally catalyzed anhydride monoester transesterification, and superior performance and reprocessability at elevated temperatures were achieved. This work provides a new idea for upcycling post-consumer polyolefin plastics, and the produced materials show great potential to be used at the industrial scale.