Fully Sustainable, Smart, and Flame-Retardant composite laminates based on epoxidized resveratrol reinforced with basalt and recycled carbon fibers

This study explores the feasibility of using a bio-based resin, epoxidized resveratrol (RESEP), reinforced with continuous basalt fibers (BF) as a sustainable composite. Furthermore, the addition of 10-oxide of 9,10-dihydro-9-oxa-10-phosphaphenanthrene (DOPO) as a flame-retardant agent, and mechanically recycled carbon fibers (rCFs) from composite production waste to obtain smart materials by developing electrically conductive composites, were also explored. The resulting composite material reinforced with rCF exhibited significant improvements in electrical conductivity, achieving up to 1.42 × 10 2 S/m, and demonstrated effective Joule effect heating, exceeding 128 ˚C with 3 V applied for a composite containing 7.5 wt% rCF. In addition, it exhibits additional multifunctional properties, serving both as a structural health monitoring (SHM) sensor (gauge factor = 94.7, superior to metallic gauges) and as an efficient de-icing device while contributing to sustainability and circularity through the use of recycled products. Adding 5 % DOPO has no measurable effect on the elastic modulus, whereas 7.5 % rCF leads to a 27 % increase. Furthermore, both RESEP-BF-DOPO and RESEP-BF-rCF laminates achieved a UL-94 V-0 rating and a high LOI of 60 %, demonstrating outstanding flame resistance and self-extinguishing properties. This study supports the advancement of sustainable and high-performance composites for the transportation sector, aligned with circular economy and emission-reduction goals.