Novel bent-shaped liquid crystalline compounds: 1. Synthesis and structure analysis of dimesogenic compounds with azo units

摘要

A new series of bent-shaped liquid crystalline compounds (2A_n), which were composed of two identical mesogens (azobenzene-type), terminal alkyloxy chains (n=6, 8, 10, 12) and 2-hydroxy-l,3-dioxypropylene as central linking unit, have been prepared. Their mesomorphic properties were characterized by polarized light microscopy, differential thermal analysis, and X-ray diffraction (XRD). For 2A_n series, n=8, 10 and 12 compounds showed enantiotropic SmC phase, but n=6 compound did not show liquid crystal phase, as was confirmed by the XRD patterns.