Rheological and curing behaviors of high heat-resistant benzoxazine resin

A new monofunctional benzoxazine resin with high char yield has been synthesized in this paper. This resin's viscosity is lower than 500 mPa s at a temerature of 55 °C, lasting for over 210 min. The experimental results on this resin's chemical rheological properties are consistent with the dual Arrhenius equation. The results of dynamic DSC analysis show that, this resin's approximate gelling temperature, curing temperature and post-processing temperature are 182.6 °C, 194.2 °C and 205.1 °C respectively. According to the Kissinger equation, this resin's activation energy of curing reaction is 78.8 kJ/mol. In addition, this resin exhibits good thermal stability: its maximum thermal decomposition rate is reached at a temperature of 479 °C, its char yield at 800 °C is 42.7 percent, and its heat-resistance index is 179.8 °C. Thus, this monocyclic benzoxazine resin is a promissing material for high performance composites.