Sustainable biobased composites manufactured via Joule heating curing with recycled carbon fibers

The use and development of thermosetting composites are limited by several complex and interconnected environmental issues, such as the continued use of fossil-based resins and the high energy demand for fibers (especially carbon fibers) and composite manufacturing. In the present research, these three criticalities are discussed, proposing the design of highly performing bio-resin and the development of thermosetting composites with recycled carbon fibers using cutting-edge, low-energy demanding processes. Exploiting the electrical conductivity of the recycled carbon fibers mat, the composites have been cured directly via Joule heating, generating heat inside the component and reaching a temperature of about 180 °C, suitable to guarantee a high curing degree of the employed thermosetting resin. Thermal parameters (temperature and heating time) have been selected based on the preliminary characterization of the biobased epoxy resin. The composites obtained using this innovative approach manifest a glass transition temperature higher than 198 °C and a complete curing degree.