Macromolecules, Vol. 38, No. 17, 2005
Copolymers Based on Fluorene and TZ 7297
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Figure 5. Current-voltage and luminance-voltage curves
of PFO-TZ50 in a device with the configuration of ITO/PEDOT/
PFO-TZ50/Ba/Al.
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A series of novel conjugated copolymers, composed of
random 9,9-dihexylfluorene and thiazolothiazole units,
were prepared via the palladium-catalyzed Suzuki
coupling reaction. All the copolymers exhibited good
solubility in common organic solvents, such as chloro-
form, toluene, and tetrahydrofuran. The introduction of
TZ moieties improved the electron transport properties
of polyfluorene. Light-emitting diodes were fabricated
using these copolymers as the emitting layer. These
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external quantum efficiency of 0.44%. The highest EL
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TZ50 (TZ content of 50%) was more than 3 times that
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