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Four new aromatic diimide–diol monomers were synthesized from bisphenol A dianhydride and hydroxyamines. The poly(ether–imide)s (PEI-1 to PEI-4) were synthesized from these diols and 4,4′-difluorobenzophenone-IV via carbonyl-activated aromatic nucleophilic fluoro displacement reaction. The chemical structures of the monomers and PEIs were confirmed by Fourier transform infrared spectrometer and proton nuclear magnetic resonance spectroscopies. The PEIs synthesized here were amorphous and soluble in polar aprotic solvents and low-boiling organic solvents. The PEIs had good thermal stability, 10% weight loss occurred in the temperatures range of 400–448°C, and char yields at 800°C under nitrogen atmosphere was in the range of 14–22%. The limiting oxygen index values of PEIs were in the range of 23.1–26.3, and such PEIs can be used as self-extinguishing polymers. The dielectric constants of the PEIs were in the range of 3.30–4.00, and such PEIs can be used as electrical insulation materials for systems operating at high temperature for long time.

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.