Circular Economy Strategy with Recyclable Thermosetting Resins

Abstract

The recycling of epoxy resins and their composites has become a serious issue due to their limited degradability. In this comprehensive review, we propose an environmentally friendly recycling system for thermosetting resins that utilizes dynamic covalent disulfide bonds in the presence of a cysteine-containing tripeptide, known as glutathione. Glutathione effectively breaks down the network structure of the epoxy resin through a thiol-disulfide exchange reaction with the incorporated disulfide bonds. The resulting recycled epoxy resin retains approximately 90 % of its initial mechanical strength. Furthermore, we explore the potential applications of disulfide-including epoxy resins as reworkable adhesives and indicators of adhesion strength. By incorporating disulfide bonds into epoxy resins, we enable their efficient recycling and offer a more sustainable solution to address the growing concern of epoxy resin waste. This innovative approach promotes the circular economy and contributes to the reduction of environmental impact associated with thermoset epoxy resin disposal.