A new series of azo-containing bent-core liquid crystals derived from 3-hydroxybenzoic acid has been synthesized. Their mesomorphic properties have been characterized by polarizing optical microscopy, differential scanning calorimetry, small-angle X-ray diffraction and electro-optic studies. Almost all the compounds form an enantiotropic modulated smectic (B7 type) phase over relatively broad temperature ranges. Structural modifications, such as the type and length of the terminal chains, the rigidity of wings, and the presence of a Cl-substituent in different positions of the bent core, affect the appearance and temperature range, but not the type of the mesophase of the investigated compounds. Light-induced changes in the texture and phase transition of the mesophase, attributed to the decrease of the order parameter due to trans-cis isomerization, have also been observed.
ASJC Scopus subject areas
- Chemical Engineering(all)