Efficient P-Conjugated Interrupted Host Polymer By Metal-Free Polymerization For Blue/Green Phosphorescent Light-Emitting Diodes

A new aromatic host polymer poly{[1,4-bis(9-decylcarbazole-3-yl)-2,3,5,6-tetrafluorobenzene-3,3-diyl]-alt-[N-methylisatin-2-one-3,3-diyl]} (PICzFB) containing carbazole-tetrafluorinebeneze-carbazole moiety in the -conjugated interrupted polymer backbone was synthesized by superacid-catalyzed metal-free polyhydroxyalkylation. The resulted copolymer PICzFB showed a comparatively wide band gap up to 3.32 eV and high triplet energy (E-T) of 2.73 eV due to confined conjugation by the C bond interrupted polymer backbone. Blue and green light-emitting devices with PICzFB as host, FIrpic and Ir(mppy)(3) as phosphorescent dopants showed the maximum luminous efficiencies of 5.0 and 27.6 cd/A, respectively. The results suggested that the strategy of incorporating bipolar unit into the -conjugated interrupted polymer backbone can be a promising approach to obtain host polymer with high triplet level for solution-processed blue and green phosphorescent polymer light-emitting diodes. (c) 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1037-1046