Synthesis and Optical Properties of Light-Emitting Polyfluorene Derivatives

The emitting-polymers, Polyfluorene (PF) and Poly(fluorene-benzothiadiazole-quinoline) [PF-BT-QL], have been synthesized by the Suzuki coupling reactions. The properties of polymers were characterized using UV-Vis spectroscopy, GPC, DSC, TGA, Photoluminescence (PL), Fluoresence (FL), Electroluminescence (EL) spectroscopy. The synthetic polymers were soluble in common organic solvents and easily spin-coated onto the indium-tin oxide (ITO)-coated glass substrates. Light-emitting devices (LEDs) with ITO/PEDOT:PSS/polymer/LiF/Al configuration were fabricated, and the devices using copolymers showed red shift EL spectra relative to that of PF. The turns on voltages of copolymers were lower than that of PF.