Co-authors​ :

 Fabrizio CAFARO (ITALY) 

Epoxy resins are highly valued for their remarkable mechanical and chemical properties, and are used extensively in various applications such as coatings, adhesives, and fiber-reinforced composites in lightweight construction. Glass and carbon fibres/thermoset matrix composites are important for the development and implementation of sustainable technologies such as wind power, energy-efficient aircrafts and electric cars. CFR and GFR composites present important properties, such as low specific mass and high mechanical strength; however, its mixture of different materials transforms them into an environmental problem, due to the complex recycling process.
This work proposes an integrated approach between a sustainable, low cost, and efficient method for the recycling of existing composites and production of new environmentally sustainable composites. Recycling of epoxy waste, was performed by in a one-step process using microwave irradiation, a mixture of hydrogen peroxide (H2O2) as a green oxidiser and tartaric acid (TA) as a natural organic acid. The process allowed the reuse of the epoxy matrix, no waste products are generated; moreover, the use of microwave irradiation allowed the reduction of both recycling time and energy consumption. The chemical residue obtained after the recycling process was first characterized by FTIR and DSC analysis. Then, the residue was used for the preparation of the recycled resin bars, obtained by mixing the product of the chemical recycling with virgin resin. Finally, thermal and mechanical properties of the produced bars were investigated by DSC and mechanical tests. To prevent the problem of recycling composite materials in the future, solutions have been proposed that involve the development of bio-based epoxy matrices (using epoxidized waste flours) and repairable/recyclable matrices (using vitrimers).