METHOD OF PRODUCING AROMATIC POLYBENZIMIDAZOLES Russian patent published in 2012 - IPC C07D235/04 C08G73/18 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing aromatic polybenzimidazoles involving formation of intermediate polyamidines in 1-Bu-3-MeImCl/AlCl₃, 1-Et-3-MeImCl/AlCl₃, 1-Bu-2,3-Me₂ImCl/AlCl₃, 1-Bu-3-MeImBr, 1-Bu-3-MeImBF₄ type ionic liquids during reaction of aromatic dinitriles with diamines at temperature 160-190°C for 15-17 hours, which further undergo oxidative dehydrocyclisation under the effect of sodium hypochlorite in the presence of a base at 100°C for 4-8 hours.

EFFECT: novel method of producing polybenzimidazoles, characterised by that synthesis takes place in milder conditions and based on stable and available monomers; possibility of increasing molecular weight of polymers; improved physical and mechanical characteristics of the materials.

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