Preparation and properties of copolymer resin based on polybenzimidazole and bisoxazoline

Reaction between the NH groups in polybenzimidazole (PBI) and bisoxazoline compounds (1,3-phenylene bisoxazoline, 1,3-PBO) resulted in the successful preparation of novel network polymers. Adjusting the amount of the bisoxazoline compound, which is a cross-linking agent for the preparation of network polymers, and obtaining dynamic mechanical measurements, electrical resistivity measurements, thermomechanical measurements, and tensile tests allowed the determination of the heat resistance and mechanical strength of these novel network polymers. Examination of the elementary reaction of PBI and the1,3-PBO curing reaction by using model compounds revealed that the NH group in the PBI structure reacted with the oxazoline group of 1,3-PBO. Comparison of noncross-linked PBI with the PBI network polymers obtained through cross-linking reaction with bisoxazoline compounds demonstrated improvements in heat resistance and mechanical strength of the PBI-bisoxazoline network polymers.