The notion that π-conjugated polymeric materials should possess interesting and useful electronic and optical properties is now well established in the scientific literature.Light-emitting polymers have revolutionized the flat-panel display technology.A large number of light-emitting polymers have been introduced during the last 10 years.Among these polymers

polyfluorenes are important class of electroactive and photoactive materials.In this thesis

a palladium-catalyzed Suzuki coupling method was used to synthesize a series of novel soluble conjugated copolymers from 9

9-dioctyfluorine (DOF) and 2

1

3-naphthoselena-diazole (NSeD).The feed ratio of DOF to NSeD are 95:5 and 99:1.The polymers are materials emitting saturated red color (650-666nm) light.The maximal emissions of devices slightly red-shifted gradually with increasing NSeD’s content.The maximal external quantum efficiency of the polymer light-emitting devices (PLED) reached 1.05%.The result indicated that the use of conjugated polyfluorene as wide band-gap segment with a small amount of narrow band-gap dopant in the polymer main chain could provide a new way to combine high quantum efficiency along with color turning ability.