Review on the synthesis of poly (imide-benzoxazole)

The new research advances in synthesis of poly (imide-benzoxazole) (PIBOs) in aprotic solvents and polyphosphoric acid (PPA) were reviewed. Traditionally, PIBOs have been synthesized via the cyclization of precursor polymers from diamine and dianhydride by a two-stage process in aprotic solvents. As result, mechanical properties of PIBOs films made by two-stage process are poor due to the presence of the holes in the process of releasing H2O molecules. In this report, it was especially elaborated that PIBOs were synthesized in PPA through one pot method. PIBO fiber with high strength was spun from PIBO/PPA dope by dry-wet spun method.