| Liquid Crystal Materials is the major division of liquid crystal display (LCD),with the rapid development of LCD development. Gem-fluoro have higher dielectricanisotropy and voltage holding ration, lower viscosity and driving voltage, quickerresponse time, which is suitable for TFT LCD. The optical properties of new liquidcrystal mixtures with it will be well improved. Therefore, these kind compounds havewide application value and more extensive application prospect. However, thesynthesis method of the Liquid Crystals materials containing gem-fluoro is immatureand has some limitations. This paper taking synthesis of monomer liquid crystalmaterials trans-4-(1,1-difluoroethyl)-4′-propyl-1,1′-Bicyclohexyl andtrans-4-propyl-4′-(2,2,2-trifluoroethyl)-1,1′-Bicyclohexyl for instance, studies on themethod of synthesis bicyclohexanes having difluoromethylyl and trifluoromethylsubstituted alkyl moiety. The following two parts are mainly studied in this paper:Part one, To designed synthesis route and purified target compound. The purity ofall these compounds is tested by GC/LC. The structure of the target compound and theimportant intermediate was characteried by MS, IR, 1H NMR, 13C NMR. The resultshows that the structures of compounds are consistent to the expected. At the sametime their reaction conditions and synthetic methods are discussed as well.Part two, The properties of target materials have been tested. The mesmorphicproperties of the target compounds were observed and measured by polarizing opticalmicroscopy and differential scanning calorimetry respectively. And the target material is added in some different liquid crystal mixtures, whose performances are tested. Itseffect in the prescription of liquid crystal materials is studied in this paper.
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