Synthesis Of Novel TFT Fluorinated Liquid Crystals

In this thesis, two types of fluorinated liquid crystals are synthesized and some compounds have been studied by both DSC analysis and thermal polarizing microscopy.The results as follows.1. A series of 1,2-bisubstituted ethane's liquid crystals containing polyfluorophenyl group:this series of compounds have high clearing point and wide temperature range of nematic phase. The phase transition temperatre is lower when the alkyl chains of compounds become longer. But the clearing point were not observed by DSC, maybe the enthalpy was so tiny that cannot be detected.2.1,2-bisubstituted ethane's compound with-CF2O-bridge:By study of the synthetic route, it was found that the acetylenic bond which connect to tetrafluorophenyl group could be hydrogenated completely by H2 with Pd/C catalyst.Liquid crystalline phase were not observed before hydrogenated.