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Some aspects of polybenzimidazoles’ synthesis in P2O5 containing condensation media

✍ Scribed by Alexey Y. Leykin; Alexander I. Fomenkov; Elena G. Galpern; Ivan V. Stankevich; Alexander L. Rusanov

Publisher
Elsevier Science
Year
2010
Tongue
English
Weight
339 KB
Volume
51
Category
Article
ISSN
0032-3861

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✦ Synopsis

The synthesis of various polybenzimidazoles (PBIs) in condensation media such as polyphosphoric acid and Eaton's reagent was accomplished. Molecular weight distribution of the synthesized polymers was examined with respect to the process conditions and the chemical structure of the monomers. It was found that during the synthesis of PBIs a side acylation reaction occurs which leads to the formation of branched macromolecules with M w up to 2.3 Â 10 6 and higher and even crosslinking, resulting in gelation of the polymers during synthesis. Fraction of the side reaction in the overall process appeared to be dependant on both the chemical structure of the monomers and the condensation media used. The orientation of the acylation reaction was determined by quantum-mechanical calculations.

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