초록 |
New polyfluorenes (PF)-based conjugated copolymers, containing carbazole units as pendants, were prepared as the electroluminescent (EL) layer in light-emitting diodes (LEDs). This new green electroluminescence polymers, CN-poly(dihexylfluorinevinylene)(CN-PDHFV), which denotes poly[(9,9-dihexyl-9H-fluorene-2,7-diyl)(1-cyanoethene-1,2-diyl)]-co-[(9-(6-(N-carbazolyl)-hexyl)-9-hexyl)-fluorene-2,7-diyl)(2-cyaoethene-1,2-diyl)], was synthesized by Knoevenagel reaction. The resulting polymers exhibit good solubility in common organic solvents and appear green emission. The UV-vis spectrum of the polymers exhibit characteristically a broad absorption band at 443, 449, 444, 445 nm respectively. These polymers show photoluminescence around λmax 550 nm (exciting wavelength 410 nm) and electroluminescence around λmax 500 nm. The highest efficiency 0.18 cd/A and which peaked at around 504 nm are reached for the device fabricated with copolymer of HS-5240 |