Synthesis and properties of polybisthienylphenylene derivatives as electroluminescent materials: improving of the photoluminescent quantum yields

Abstract

Poly[1,4-bis(4-alkyl-2-thienyl)-2,5-disubstituted phenylene]s and their monomers have been regioselectively synthesized in high yield. The head-to-head defined structures of all polymers and monomers are demonstrated by FT-IR, ¹H, ¹³C NMR and elemental analysis. All new materials exhibit good thermally stability, optical, electrochemical properties. Their HOMO and LUMO energy levels are determined by cyclic voltammetry and UV-vis measurement. The improvement of absolute PL quantum yields of all six polymers in the solid films have been approved after the aromatic groups were introduced into the main chain of polythiophene. Three materials were chosen to be fabricated as single layer LED devices.