Synthesis and characterization of pyridine and anthracene containing bismaleimides, bisnadimides and polyaspartimides

Three different novel diamines containing pyridine and anthracene moiety were prepared and subsequently converted into bismaleimides (BMI) and bisnadimides (BNI) and their structure was confirmed by elemental analysis, FT-IR, H-1-NMR and C-13-NMR techniques. Chain extension of bismaleimides and bisnadimides was accomplished by incorporating various ether or ester groups. Owing to pendant anthracene moiety, pyridine unit and flexible linkages, the bismaleimides and bisnadimides were found to possess an excellent balance of properties; solubility and thermal stability and the curing behaviour was investigated by differential scanning calorimeter. In addition, a series of polyaspartimides containing anthracene and pyridine unit was prepared by the polyaddition of bismaleimides with various diamines via a Michael-type addition. The thermal stability of bismaleimides, bisnadimides and polyaspartimides was evaluated by thermo gravimetric analysis. All the polyaspartimides are soluble in many organic solvents and exhibit T-g in the range of 189-242 degrees C and 10% weight loss (T-10) takes place in the range of 389-487 degrees C in N-2.