Synthesis of new biobased benzoxazine through green strategy and its polybenzoxazine resin with high thermal resistance and mechanical strength

Benzoxazine resins from benzoxazine monomers synthesized with green strategies often do not have high thermal resistance and mechanical strength. Herein, starting from renewable resources citraconic anhydride, furfurylamine and tyramine, a new benzoxazine monomer ( CT-fa ) was synthesized and purified in green solvents (ethanol and ethyl acetate), which has excellent molding processability reflected by low melting point (84.9 °C) and low curing temperature (207–245 °C). More attractively, the cured CT-fa resin ( poly(CT-fa) ) has both high glass transition temperature (281 °C) and high initial thermal decomposition temperature (407 °C), the former is higher than those of all monofunctional benzoxazine resins synthesized though green strategies in literature, and the latter is even higher than those of all benzoxazine resins synthesized by green strategies (SCI database). In addition, poly(CT-fa) also has high storage modulus (3955 MPa) and good tensile strength (51.60 MPa). These attractive properties demonstrate that poly(CT-fa) is a promising green high performance resins. Graphical