The mesomorphic properties of two series of fluorine substituted liquid crystals containing three rings were systematically characterized to investigate their phase transition behavior using differential scanning calorimetry(DSC)
microscopy heat analysis and polarizing optical microscopy(POM). The results show that all the compounds except 2CPPF
3
and 4CPPF
3
possess mesomorphism. Typical textures of smectic and nematic phase were observed. The influence of terminal alkyl
core structure and the number of fluorine substituents on the temperature of phase transition was discussed.
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