Epoxy Vitrimer Formulation for Resin Transfer Molding: Reactivity, Process, and Material Characterization

Initially bound for landfill or incineration due to strong limitations in their repair or recycling, thermoset composite materials have recently received considerable attention in order to improve their end-of-life. In this respect, vitrimers appear to be a solution of choice, as they possess the capability for topological reconfiguration through an associative exchange mechanism, imparting them glass-like properties at high temperatures. However, despite these advances, studies with particular focus on the process such as pultrusion, impregnation, and resin transfer molding (RTM) remain scarce. In this work, a detailed reactivity study was conducted on a vitrimer formulation based on disulfide exchange chemistry toward the RTM process, which includes the development of a time–temperature–transformation (TTT) diagram. On this basis, vitrimer plates were successfully prepared by RTM, yielding thermal and mechanical properties similar to the reference epoxy resin. Additionally, while exhibiting very competitive properties, the resulting vitrimer materials demonstrated the ability to be reshaped and reprocessed. This work covers resin formulation, reactivity, implementation into the RTM process and, ultimately, material and mechanical characterization.