Upcycling of waste thermosets into multiple-responsive supramolecular materials via acid-catalyzed oxidation

Abstract

Many recovery strategies have been proposed since vast of plastic wastes pose a threat to environment, but adding value and tackling circularity are still challenging. Herein, we report the direct converting of waste epoxy resins into multiple-responsive (temperature, water and pH) supramolecular materials via acid-catalyzed oxidation. In the degradation process, we find the effective synergism of hydrogen peroxide and protonic acid, where protonic acid activates C–N bonds of the thermosets and enhances mass transfer, while hydrogen peroxide attacks them to produce oligomers with abundant functional groups. Thus, the oligomers as building blocks assemble into polymers through hydrogen bonds. This design allows non-recyclable thermosets into value-added and recyclable new materials, pointing out a sustainable way to circumvent environmental and resource issues caused by plastic wastes. This work is also expected to impact materials science of designing split-new functional materials.