Hochmolekulares, in THF lösliches Poly(2,7‐fluorenylen‐1,2‐diphenylvinylen) 4 wird durch Dehalogenierungspoly‐kondensation mittels Chrom (II) acetat aus 2,7‐Bis(α,α‐dichlorbenzyl) fluoren gewonnen. Das Monomer ist aus Fluoren über 2,7‐Dibenzoylfluoren und dessen Umsetzung mit PCl5 zugänglich. 4 ist ein ausgezeichneter filmbildender Photoleiter mit hohem Dunkelwiderstand, einer Glastemperatur Tg = 247°C und guter Thermostabilität (TZers. = 555°C). Es wird über die spektrale Verteilung der Photoleitfähigkeit sowie ihre Sensibilisierung durch 2,4,7‐Trinitrofluorenon berichtet. Die chemische Struktur des Linearpolymers 4 wird durch CH‐Analyse und spektroskopische Methoden (13C‐NMR, 1H‐NMR, IR, UV‐VIS) belegt. Die Molmassenverteilung wird über GPC untersucht, und es werden M̄n (VPO)‐Messungen mitgeteilt.

Soluble poly(9-methylcarbazole-3,6-diyl-1 ,2-diphenylvinylene) (1) & = 10 000, was prepared by dehalogenating polycondensation of 3,6-bis(a,a-dichlorobenzy1)-9-methylcarbaole with chromium(I1) acetate. The monomer was obtained from 3,6-dibenzoyl-9-methylcarbazole by reaction with PCl, . The chemical structure of 1 was verified by elemental analysis, UV, IR, and NMR spectroscopy, GPC, and VPO. 1 was found to be highly photoconducting, exhibiting a dark conductivity of S/cm. Its thermal stability under nitrogen is as high as with other phenylsubstituted poly(ary1eneviny-1ene)s (dec. temp.: 540 'C; residue: 72 weight-%). The spectral distribution of sensitized (TNF, dyes) photoconductivity was studied and the redox behaviour was investigated by cyclovoltammetry. The redox potentials were found to be @; 2 = 0,90 V and ESd = -2,07 V (vs.Ag/AgCl). The electrochemical oxidation is reversible, associated with the formation of polydications derived from chain segments which consist of two carbazolediylvinylene units. Thus, 1,2-dicarbazole-3-yl-1,2-diphenylethylene as model compound well reflects the redox properties of the polymer. The electrochemical band gap energy was found to be 2,97 eV, which agrees closely with the energy of the optical absorption edge of 3.04 eV.S/cm, which increases on doping with AsFs to

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