Year: 2024
Type: article
Abstract: Cleavable bio-based epoxy resin systems are emerging, eco-friendly, and promising alternatives to the common thermoset ones, providing quite comparable thermo-mechanical properties while enabling a circular and green end-of-life scenario of the composite materials. In addition to being designed to incorporate a bio-based resin greener than the conventional fully fossil-based epoxies, these formulations involve cleaving hardeners that enable, under mild thermo-chemical conditions, the total recycling of the composite material through the recovery of the fiber and matrix as a thermoplastic. This research addressed the characterization, processability, and recyclability of a new commercial cleavable bio-resin formulation (designed by R-Concept company) that can be use in the fabrication of fully recyclable polymer composites. The resin was first studied to investigate the influence different post-curing regime (room temperature, 100°C, and 140°C) on its thermal stability and glass transition temperature. According to the results obtained, the non-post-cured resin displayed the highest Tg (i.e., 76.6°C). The same post-curing treatments were also probed on the composite laminates (glass and carbon) produced via a lab-scale vacuum-assisted resin transfer molding system evaluating the flexural behavior, microstructure and dynamic-mechanical characteristics. The post-curing at 100°C would enhances the crosslinking of polymer chains, improving the mechanical strength of composites. With respect the non-post-cured laminates, the flexural strength improved by 3% and 12% in carbon and glass-based composites, respectively. The post-curing at 140°C was instead detrimental for the mechanical performance Finally, on the produced laminates, a chemical recycling procedure was implemented, demonstrating the feasibility of recovering both thermoplastic-based resin and fibers.
Source: Polymers
Language: English
Topic: Epoxy Resin Curing Processes
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,069
Awards: G1585674959, G482427013
OpenAlex ID: W4405968661