Thermal stability of silicon-containing amide benzimidazole,hydrazide, and oxadiazole polymers

Studies were undertaken to ascertain the thermal stability of several types of silicon-containing polymers. Results of thermal analysis investigations indicate that all of the polymers are unusually heat-resistant when heated in air at elevated temperatures. Solution-cast films of the polymers on aluminum showed excellent flexibility and adhesion characteristics after being heated in air for 100 hr. at 300°C. and then for 3.5 hr. at 400°C. Visual examination of the films after the heating sequence indicated that the silicon-containing polyamides and polybenzimidazole had darkened slightly, while the polyoxadiazole appeared to be unaffected in this respect. Infrared spectroscopy studies showed that all of the polymers underwent only very minor structural changes during the prolonged heating process.