Synthesis and characterization of poly(terphenylenevinylene) derivatives containing alkoxy substituents and (or) phenyl pendant group

The blue electroluminescent polymers, poly(terphenylenevinylene) derivatives that have advantages of PPP and PPV, were prepared by Suzuki coupling reaction. The structure and properties of the polymers were analyzed by various spectroscopic methods. Poly(MHTPPV) and poly(TPPV) with phenyl pendant group in a vinyl bridge showed blue shifted absorption spectra, large band gap and enhanced thermal stability as compared with that of poly(MHTPV). The PL spectra of the films of the polymers showed maximum peaks at 450-460 nm, which are pure blue emissions. The blue electroluminescence (lambda(max) = 450-460 nm) was obtained with the turn on voltage of 8-10 V, when the simple light-emitting diodes of ITO/polymer/Al were fabricated. The excimer emission due to interchain interaction was reduced by the introduction of substituents into the vinyl bridge and (or) the main chain. (C) 2004 Elsevier Ltd. All rights reserved.