A novel bio-based benzoxazine resin with outstanding thermal and superhigh-frequency dielectric properties

A novel bio-based benzoxazine was synthesized from diphenolic acid and furfurylamine through the facile one-pot formulation method. In comparison with other bio-based thermosetting resins and bio-based benzoxazine resins, the prepared benzoxazine resin had the advantages of accelerated curing behavior, relatively good thermal properties (T_g, 303 °C; char yield (800 °C), 54%), and relatively low superhigh-frequency dielectric constants (2.97 ± 0.01, 5 GHz; 2.95 ± 0.01, 10 GHz; 2.90 ± 0.01, 15 GHz), resulting from the introduction of acidic groups and furan rings. Therefore, this work not only provides a new strategy for the preparation of biomass-based benzoxazine resin with superhigh-frequency low dielectric constants, but also gives some insight into the effects of pentanoic acid and furan rings on the curing behavior, cross-linking structure, and thermal and superhigh-frequency dielectric properties of benzoxazine resin. Furthermore, the potential application of this approach in the advanced superhigh-frequency communication field might make progress towards the sustainable development of high-tech polymeric industry.