Synthesis and properties of new polybenzimidazoles and N‐phenyl polybenzimidazoles with flexibilizing spacers on the polymer backbone

摘要: Several new polybenzimidazoles (PBIs) and N-phenyl PBIs were synthesized by high temperature solution polycondensation techniques. Three different tetramine hydrochlorides one hydrochloride condensed independently with p-phenylenedioxydiacetic acid (PDDA), 2,2′-[isopropylidene bis(p-phenyleneoxy)] diacetic (bisacid A2) 2,2′-[sulfonyl S) in polyphosphoric (PPA) at temperatures. The polymers obtained 55–65% yield inherent viscosities the range 0.58–0.96 dL/g. Four model benzimidazoles (MBI) also to confirm formation of polybenzimidazoles. MBIs characterized infrared spectroscopy elemental analysis. properties such as solubility, density, crystallinity, thermal, thermoxidative, isothermal stabilities studied.