Synthesis and characterization of novel germanium-containing poly(p-phenylenevinylene) derivatives

Novel blue-emitting germanium-containing poly(p-phenylenevinylene) (PPV) derivatives with well-defined conjugation lengths were synthesized via Wittig-condensation polymerizations. The polymers can be color-tuned by the introduction of various chromophores into the PPV-based polymer backbones. The photoluminescence (PL) spectra of the polymers, GePVK (containing carbazole moieties), GeMEH (containing dialkoxybenzene moieties), and GePTH (containing phenothiazine moieties), were found to exhibit blue, greenish blue, and green emissions, respectively. GePTH produces more red-shifted emission than GeMEH and GEPVK, resulting in green emission, and the solution and solid state PL spectra of GePVK consist of almost blue emission. The electroluminescence spectra of GeMEH and GePTH contain yellowy green and yellow colors, respectively. Interestingly, GePVK exhibits white emission with CIE coordinates of (0.33, 0.37) due to electroplex emission in the light-emitting diodes. (C) 2007 Wiley Periodicals, Inc.