Sustainable Preparation of Bio-Based Polybenzoxazine Resins from Amino Acid and Their Application in CO2 Adsorption

A series of new biobased benzoxazine monomers were synthesized by reacting amino acid methyl ester and disphenolic acid methyl ester/eugenol (E) with paraformaldehyde by Mannich condensation reaction. The chemical structures of these biobenzoxazine monomers were characterized by 1H NMR, 13C NMR, mass spectrum, and Fourier transform infrared (FTIR). Their curing behaviors were examined by differential scanning calorimetry (DSC) and FTIR spectroscopy. Thermogravimetric analysis was utilized to evaluate the thermal stability of the polybenzoxazines. The poly(E−lyme) showed highest thermal stability in these obtained biothermosets, Td10% of 373 °C and char yield of 47%, respectively. Furthermore, these polybenzoxazines showed good application in the CO2 adsorption field as the carbon precursor, and the activated carbon materials from poly(E−lyme) had a high surface area of up to 1194 m2 g–1. The remarkably high CO2 adsorption capacity of 5.82 mmol/g was observed on the carbon material ELF0 at 800 mm Hg and 273 K.