Bipolar poly(p -phenylene vinylene)s bearing electron-donating triphenylamine or carbazole and electron-accepting quinoxaline moieties

Two new poly(phenylene vinylene)s (PPVs) carrying electron-donating triphenylamine or carbazole and electron-deficient quinoxaline units were synthesized and characterized. Their properties were compared with those of PPV containing only quinoxaline unit. The two polymers showed PL maximum at 501–510 in solution and 533–540 in thin film. Because of the presence of electron donor and acceptor units they displayed strong intramolecular charge transfer (ICT) effects; hence, low-photoluminescence quantum yields. The polymers showed reversible electrochemical reduction with electron affinity of 2.75 eV and irreversible oxidation with ionization potential of 5.10–5.24 eV. Single-layer LED of configuration ITO/PEDOT/polymer/Al showed low turn-on voltage at 5 V, but limited brightness of 50–60 cdm−2. The electroluminescence maximum was voltage-tunable varying from 500 to 542 nm. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2367–2378, 2008