Circular Economy Potential of Sustainable Bio-Based Composites: Repair, Recycle and Reuse

Bio-based materials are increasingly recognized as sustainable alternatives to fossil resource-based materials, aligning with circular economy principles. However, the thermosetting nature of bio-based epoxy systems poses a significant challenge, lim-iting their suitability for conventional repair and recycling methods commonly ap-plied to thermoplastics [1]. This limitation complicates the management of their end-of-life scenarios, raising concerns about sustainability. To address these challeng-es, efforts have been directed toward integrating bio-based precursors into trans-esterification vitrimers, leading to the creation of advanced bio-based vitrimer sys-tems that align with green chemistry principles. The QB3R project (Quality controlled high-performance components consisting of 100% bio-based resins with high po-tential for repair and recycling) is at the forefront of this approach. The focus of this research project is on the development of a 100% bio-based material system com-posed of natural fibers and bio-based polymers. The project explores various manu-facturing techniques to process this system and demonstrates its applicability in me-chanically demanding applications through the production of a sledge demonstrator. Additionally, it aims to analyze the vitrimer functionality of the material, exploring repair options via matrix re-linking and re-infiltration [2]. The project also investigates the mechanical recycling potential and material re-use within the composite pro-cessing [3], contributing to the advancement of sustainable composites within a cir-cular economy framework.