Synthesis and mesomorphic properties of mesogens containing 1,1,2,2-tetrahydroperfluorodecaoxy terminal chains

One series of two-ring and two series of three-ring mesogens with 3,3,4,4,5 5,6,6,7,7,8,8,9,9 10,10-heptadecafluorodecaoxy terminal chains containing tolane or biphenyl units have been synthesized. Their mesomorphic propertie s were observed and measured by optical polarizing microscopy and different ial scanning calorimetry. The three-ring mesogens only exhibit a wide smect ic C phase when the length of their hydrocarbon chains is intermediate.