Synthesis and properties of the polymers containing 3,3′-dicarbazyl units in the main chain and their model compounds

The polymers containing 3,3'-dicarbazyl moieties in the main chain have been synthesized by dehalogenative condensation of 1,6-di(3-iodo-9-carbazolyl)alkanes. The number-average molecular weights of the polymers synthesized were in the range of 1900-6000 with a molecular weight distribution of 2.2-2.5. The model compounds of the polymers 9,9'-dialkyl-3,3'-bicarbazoles have been synthesized by stepwise reactions. All these compounds have been found to form glasses with glass transition temperatures in the range of 71-169 degreesC as characterised by differential scanning calorimetry. The electron photoemission spectra of the compounds have been recorded and the ionisation potentials of 5.46-5.57 eV have been established. Hole drift mobilities of 3.6 x 10(-6) and 2.8 x 10(-5) cm(2)/V s were observed in the amorphous films of the polymer and of the dimer model compound, respectively, by the time of flight technique at an applied field of 6.4 x 10(-5) V/cm. (C) 2002 Published by Elsevier Science Ltd.