Synthesis and polymerization of benzoxazine molecules with electron-withdrawing group substitution and ring-opening polymerization

The synthesis of strong electron-withdrawing group substituted aromatic amine and phenol-based benzoxazines is hampered due to the poor solubility of the reactant. In this article, a simple methodology is presented to synthesize the strong electron-withdrawing groups substituted benzoxazine monomers from a solution method using a low-boiling polar solvent. In order to achieve this, we used formaldehyde as a reactant as well as a solvent, and the reaction was carried out for a longer time. Also, benzylaniline derivatives were successfully prepared through benzoxazine. The monomers were polymerized by using solution polymerization method using lithium bromide as a catalyst. The structure of the monomers and polymers was confirmed by Fourier transform infrared and nuclear magnetic resonance spectroscopy. The thermally activated polymerization of the monomers was evaluated by differential scanning calorimetry, and thermal properties of polymers were analyzed by thermogravimetric analysis.