SYNTHESIS AND MESOMORPHIC PROPERTIES OF FERROELECTRIC LIQUID-CRYSTALSBEARING 2-PHENYL-1,3,4-THIADIAZOLE RINGS

Sixteen homologs of chiral 2-phenyl-1,3,4-thiadiazoles were synthesize d and their mesomorphic properties were evaluated with a DSC and a pol arizing microscope. All compounds studied possessed an alkyl or alkoxy side chain at the p,p' position of the 2-phenyl-1,3,4-thiadiazole cor e and an optically active carbon atom at one of the terminal chains. W e found that compounds in these series show a strong tendency to gener ate chiral smectic C (Sc+) phases. We also measured some compounds for their spontaneous polarizations (Ps) and switching times (tau) and fo und that the switching times were relatively fast, though the spontane ous polarizations were very small.