Synthesis and characterization of new thermally stable poly(ether-imide)s derived from 4-aryl-2,6-bis[4-(3-nitrophthalimido)phenyl] pyridines

A series of thermally stable poly(ether-imide)s (PEI1-16) bearing bulky aryl pendant groups were synthesized by nitro-displacement condensation of a new series of dinitrobisimide monomers, namely 4-aryl-2,6-bis[4-(3-nitrophthalimido)phenyl]pyridines (DNBI1-4), with commercially available aromatic diols (DO1-4). These dinitrobisimides were prepared from the reaction of 4-aryl-2,6-bis(4-aminophenyl)pyridines (DA(1-4)) and 3-nitrophthalic anhydride in N,N-dimethyl acetamide. A model compound was synthesized by reaction of DNBI1 with phenol in the presence of potassium carbonate in dimethyl formamide and the resulting bis(ether-imide) derivative was obtained in high yield. These polymers were characterized by FT-IR, H-1-NMR and elemental analysis, and their physical properties, including solution viscosity, solubility properties and thermal stabilities, were studied. The synthesized PEIs show excellent thermal stability and solubility in polar aprotic solvents.