In this study, a new synthesis of polybenzoxazoles was studied by reacting 3,31-dihydroxy-4,41diaminobiphenyl with various p-aromatic dihydroxamoyl chlorides in N,N-dimethylformamide under a nitrogen atmosphere at both room temperature and 150 3C. The polymers were characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, liquid chromatography/mass spectrometry, thermogravimetric analysis and the elemental analysis. Direct current conductivity of HCl acid-doped polybenzimidazole pellets was measured by applying a constant voltage of 5 V. The results of this study are discussed herein.
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