Cobalticenium-bridged polybenzazoles. 1. Low temperature solution polymerization.
In: Polymer (Polymer), Jg. 17 (1976) ; Nr. 5, S. 423-428
Zeitschriftenaufsatz / Fach: Chemie
Low mol. wt. amide-linked 1,1'-bis(chlorocarbonyl)cobalticenium chloride-1,1'-bis(chlorocarbonyl)cobalticenium hexafluorophosphate-3,3'-diaminobenzidine copolymer (I) and amide- and thioester-linked 1,1'-bis(chlorocarbonyl)cobalticenium chloride-1,1'-bis(chlorocarbonyl)cobalticenium hexafluorophosphate-3,3'-dimercaptobenzidine copolymer (II) [60311-17-3] were prepd. by low-temp. soln. polymn. The Cl ions in I and II were substituted by PF6 by pptn. from NH4PF6-HCO2H. The 4 copolymers underwent cyclization at <300 Deg, e.g. I and II gave bibenzimidazole polymer III and bibenzothiazole polymer IV. The cyclized polymers had thermal stability and soly. inferior to those of phenylene-bridged bibenzimidazoles.