1,3,4-oxadiazole moieties were laterally linked to the phenyl rings via a short -OCH2 spacer and a series of novel poly(p-phenylenevinylene) derivatives have been successfully synthesized through Horner-Witting-Emmons coupling reaction. The structures and properties of the monomers and the resulting conjugated polymers were characterized by nuclear magnetic resonance spectroscope, Fourier transform infrared, elemental analysis, gel permeation chromatography, thermogravimetric analysis, UV-vis absorption (UV) spectroscopy, photoluminescence spectroscopy and cyclic voltammetry. The UV spectra at solution state was similar to what's observed at film state while the PL spectra at film state had a red shift from 19 to 28 nm compared with the results at solution state, which implied that the unique bulky jacketed structure containing oxadiazole unit of these copolymers could effectively suppress pi-stacking/aggregation. LUMO levels of these polymers varied from -3.44 to -3.63 eV with increasing content of oxadiazole units, which facilitated electron injection. PLEDs with the configuration of ITO/PEDOT/Polymer/TPBI (15 nm)/LiF (1 nm)/Al (100 nm) were fabricated, which emit a yellowish green light around 540 and 570 nm with a maximum brightness of 1074.7 cd/m(2) and luminous efficiency of 0.108 cd/A. The introduction of the unique bulky OXD unit into PPVs at a low molar content largely improved the electroluminescence properties of PPV. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7173-7186, 2008