Design and\nEvaluation of a Reprocessable Bismaleimide\nThermoset: Enhancing Functionality and Sustainability Compatibility

Bismaleimide (BMI) resins are high-performance thermosets\nthat\nare primarily used in aerospace because of their exceptional heat\nresistance and physical properties. However, their growing demand\nhas led to significant environmentally unfriendly waste. To address\nthis, our research proposes a reprocessable BMI system using a newly\nsynthesized BMI vitrimer (BMIV) with functional groups that form covalent\nadaptable networks (CANs). To enhance the properties, a symmetrical\nBMI with two ester groups introduced into the rigid rod molecule was\ndesigned as a CAN component. After confirming the structure using\nvarious spectroscopic techniques, BMIV was coupled with aromatic diamines\nvia an additional aza-Michael reaction to obtain the cured resins.\nSubsequently, the mechanical properties and reprocessing behavior\nof the thermally stable and optimized thermosetting material with\nthe best performance were evaluated, and the evidence, mechanism,\nand activation energy of the topology rearrangement are reported in\ndetail.