| 초록 |
For the development of polymer light-emitting diodes(PLEDs), stable and efficient blue light emission is of particular importance. In blue polymer LEDs, 9,9 disubstituted poly(2,7-fluorene)s(PFs) are the most promising materials because of high photoluminescence(PL) and electroluminescence(EL) quantum efficiencies and high EL brightness. In PLEDs films, aggregates do form in many instances. This aggregation process is widely believed to be responsible for the strong decrease in luminescence quantum yield as well as a red shift in the PL spectrum observed in the solid state. We synthesized novel spiro-branched polyfluorenes with a new spiro-synthetic route. p-Alkylated hetero atoms were in situ cyclized with fluorenone resulting in spiro-annulated structures. These PF derivatives not only minimize the close packing but also tune the energy level for better charge injection. |
