Synthesis, spectroscopy and electrochemistry study on a novel di-silyl substituted poly(p-phenylenevinylene)

A novel di-silyl substituted poly(p-phenylenevinylene) (PPV) derivative is synthesized through the Gilch route. The polymer is solution processable an d shows high thermal stability in air. UV-Vis spectra for the film and solu tion samples illustrate some different features, in which the absorption pe ak corresponding to die pi-pi* transition of the delocalized electrons alon g the polymer back bone is red shifted and broadened in the film state comp ared to the solution one. The fluorescent emission spectra are quite simila r for the polymer in solution and in the solid states. Cyclic voltammetric investigation reveals a partially reversible n-doping process and an irreve rsible p-doping process. The cathodic current is much greater than that of the anodic one, which means the polymer has the tendency to be charged thro ugh n-doping rather than p-doping process. The improved affinity of the pol ymer to electrons may be owing to the low interface barrier between the pol ymer films and the electrode surface. The HOMO and LUMO energy Bevels have also been estimated from the data of oxidation and reduction onset potentia ls. All of the results indicate that the synthesized polymer is a promising green emissive material for the light-emitting device application. (C) 199 9 Elsevier Science S.A. All rights reserved.