Polybenzimidazole’s (PBI) was synthesized from 3,3’-diaminobenzidine and adipic acid by melting copolycondensation. Its thermal properties have been studied The molecular structure and thermal stability of the resulting polymers were characterized by means of FTIR, TGA and DSC. The results indicate that the melting temperature of the PBI is higher than 400°C and the polymer possesses excellent thermal stability. The onset decomposition temperature was determined to be 516°C, and the highest decomposition temperature reaches 536°C.
