High-performance and fire-resistant epoxy thermosets derived from plant-derived ferulic acid

Development of epoxy thermosets derived from biomasses with intrinsic flame retardancy and high mechanical performances is of increasing demand. Here we synthesize a novel epoxy monomer (DGEFA) from ferulic acid that can be directly obtained from many plants and offers intrinsic flame retardancy due to its conjugation structure. By using 4,4’-diaminodiphenylmethane (DDM) as a curing agent, the cured epoxy resin (DGEFA-DDM) possesses a high glass transition temperature (178.5 °C). The DGEFA-DDM also exhibits high mechanical performances, i.e., tensile strength of 84.7 MPa and flexural strength of 145.1 MPa. Besides, the DGEFA-DDM presents a char yield of 40.6 % under N2, a V-1 rating of UL-94 and a limiting oxygen index of 32.8 %. The cone calorimeter test shows that the DGEFA-DDM has low heat and smoke release performances with a total heat release of 49.2 MJ/m2 and a total smoke production of 16.0 m2, indicating a high intrinsic flame retardancy. This work provides a simple way for the preparation of epoxy resins from bio-based feedstocks possessing physical properties and fire safeties.