DCZB moieties

These polymers are prepared by polycondensation reactions. Polyurethanes containing DCZB moieties in the main chain (26a) were prepared by treating trans-l,2-bis(3-hydroxymethyl-9-carbazolyl)cyclobutane with the corresponding diisocyanate in the presence of dibutyltin dilaurate [204]. The relative molecular mass of the polymer synthesized using hexamethylene diisocyanate as a linking agent was 2700, and that of the polymer prepared with toluylene diisocyanate was 16000. Polymers (26a) exhibit almost exclusively monomer fluorescence in dilute solution, i.e. they practically have no intramolecular excimer-forming sites. Their complexes with TNF show better photoconductivity than PVK-TNF. 

Poly-SchifF bases containing DCZB units in the main chain (26b) were synthesized by the direct polycondensation of rran5-l,2-bis(3-formyl-9-carbazolyl)cyclo-butane with aromatic diamines [217]. Complexation of the polymers (26b) with iodine produces cation-radical salts which result from an electron transfer from DCZB moieties to iodine. The undoped polymers are insula-... 

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