Synthesis and Characterization of New Organosoluble and Thermally Stable Polyimides Containing Pyridine and Anthracene Units

A series of new polyimides were obtained by the polycondensation reactions of the three diamines containing pyridine and anthracene units with various aromatic tetra carboxylic dianhydrides via both two-step and one-step methods. The precursors and monomers were characterized by elemental analysis, FT-IR, H-1-NMR and C-13-NMR techniques. The structure of the polyimides was confirmed by FT-IR, and H-1-NMR spectroscopy, inherent viscosity and molecular weight measurements. All the polyimides are soluble in aprotic solvents such as NMP, DMF, DMAc and DMSO. These polyimides exhibit T-g in the range of 213-317 degrees C and 10% weight loss (T-10) takes place in the range of 414-531 degrees C in N-2 401-521 degrees C in air and the char yield varies between 38-54%. The polymer films have tensile strength in the range of 84-110 MPa, elongation at break in the range of 11.2-13.8% and tensile modulus in the range of 1.1-1.4 GPa and low moisture absorption (0.87-1.16). All of these new polymers show excellent thermal stability and the polyimide films have good mechanical properties.