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

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