Novel light-emitting polymers derived from fluorene and maleimide

A series of novel soluble light-emitting polymers derived from fluorene and maleimide were synthesized by a palladium-catalyzed Suzuki coupling reaction. The resulting polymers were characterized by NMR, FT-IR, elemental analysis, DSC, TGA and GPC. These polymers show very strong yellow PL emission and good solubility in common organic solvents, such as CH2Cl2, CH3Cl, toluene and xylene. DSC and TGA studies reveal that the novel polymers possess excellent thermal stability with high glass transition temperatures (T-g) and onset decomposition temperatures (T-d). Cyclic voltammetry measurements demonstrated that the polymers have high electron affinity and good hole and electron transporting properties. Light emitting diodes (LEDs) with the configuration ITO/PEDOT : PSS/polymer/Mg:Ag were fabricated. All the LEDs show low turn-on voltages and good electroluminescence properties with yellow emission.