| 초록 |
Isotropic light reduces the efficiency of the OLED by 50% as it passes through the polarizer of devices. However, when circularly polarized light is generated in the emission layer of the device, it can reduce the loss of efficiency. In particular, light can be polarized in a specific direction due to the inherent anisotropic property of the mesogenic materials. In this study, chiral flexible chains were introduced into the central as well as terminal positions in the mesogenic unit, which were suitable to exhibit cholesteric liquid crystal phase and circular polarized light emission. The fluorene derivatives were synthesized through Williamson etherification and Suzuki coupling reaction. Structure of compounds were identified by 1H-NMR and FT-IR spectrometry. Their thermal and liquid crystalline behaviors were investigated by DSC and POM. Absorption and luminescence properties were investigated by UV-Vis and PL spectrometry. Polarimeter was used to measured the chirality of compounds. |
