High-Performance Bio-Based Benzoxazines from Enzymatic Synthesis of Diphenols

This paper reports the preparation, characterization, and performance of three low viscosity fully bio-based benzoxazine resins synthesized from bio-based furfurylamine, paraformaldehyde, and three new enzymatic originated diphenols obtained through a sustainable and highly selective lipase-catalyzed enzymatic process from p-coumaric acid, and three bio-based diols (propanediol, butanediol, and isosorbide, respectively). The enzymatic method is used for the first time, to the authors' knowledge, to design specific diphenolic structures dedicated to the preparation of benzoxazine thermosetting resins whose precursors exhibit easy handling within a wide processing window (from room temperature up to 200 degrees C). The resulting cross-linked materials present high glass transition temperature (T-g > 200 degrees C) and inherent charring ability upon pyrolysis (approximate to 50 wt% at 1000 degrees C). These results open a valuable and new pathway to develop enhanced benzoxazines and bring them new properties.