Synthesis of polyamidines based on aromatic bis(imidoyl) chlorides in solution

New amidine-containing polymers were prepared by the polycondensation of aromatic diamines with bis(imidoyl) chlorides in polar organic solvents in the presence of various catalysts (triethylamine, tributylamine, and pyridine N-oxide). Optimal synthesis conditions, namely, temperature, duration, concentration of monomers and catalyst, and the order of reagent loading, were established. The structure of polyamidines was studied by elemental analysis and IR and NMR spectroscopy. When the polymers were heated to 250°C in vacuum, their molecular masses increased.