Design and Synthesis of Bio-Based High-Performance Trioxazine Benzoxazine Resin via Natural Renewable Resources

Abstract

A new fully biobased trioxazine benzoxazine is synthesized by reacting resveratrol, furfurylamine, and paraformaldehyde via the Mannich condensation reaction. The chemical structure of this biobenzoxazine is characterized by 1H and 13C nuclear magnetic resonance and Fourier transform infrared (FT-IR) spectroscopies. 1H-1H nuclear Overhauser effect spectroscopy is utilized to unambiguously identify the isomer obtained. Monomer polymerization is investigated by differential scanning calorimetry and in situ FT-IR. Thermal stability of the fully polymerized polybenzoxazine is evaluated by thermogravimetric analysis, and flammability is assessed by microscale combustion calorimetry. The biothermoset obtained shows high thermal stability and low flammability, Td10 of 403 °C and char yield of 64%, respectively, low heat release capacity (54 J/gK), and low total heat release (9.3 KJ/g), thus exhibiting self-extinguishing and nonignitable properties. Consequently, this new fully biobased trioxazine benzoxazine and its corresponding polybenzoxazine possess excellent processability and thermal properties, suggesting great potential toward high-performance and fire-resistant materials.