Synthesis and properties of polybenzazoles containing flexible methylene in backbone

Abstract

A novel series of polybenzazoles with rigid-rod benzoxazole cycle and soft methylene segment was designed and synthesized via solution condensation polymerizations from 4,6-diamino-1,3-benzenediol diphosphate, terephthalic acid and aliphatic dicarboxylic acid. The structures of polybenzazoles were characterized by means of FT-IR, ¹H NMR and Wide-angle X-ray diffraction (WAXRD). All the polymers show excellent thermal stability and the T_ds was above 471°C. The intrinsic viscosities [?] of the polymers ranged from 0.8 to 0.9. The UV-Vis absorption peaks of the polymers in MSA were blue-shifted from 429 nm for PBO to 291 nm for PBOC7, and the Stokes shifts in PL spectra enlarged.

Keywords

polybenzazole / aliphatic dicarboxylic acid / synthesis and characterization / photophysical property / stokes shift