Synthesis and Phase Behaviors of New Heterocyclic Liquid Crystals: Nematic and Smectic Properties

Abstract:

A series of new rod-shaped liquid crystal, 6-methoxy-2-(4-alkyloxybenzylidenamino) benzothiazoles possessingeven numbers of carbon atoms at the alkyloxy chain (C_nH_2n+1O-, n = 10, 12, 14, 16, 18) are prepared and characterized. The phase behaviour of these new compounds was studied by differential scanning calorimetry and polarising optical microscopy. All members exhibited mesophase. Influence of alkyl chain length on the mesomorphic properties was studied. Enantiotropic nematic phase was identified in all the members except for n = 18. Lower member (n = 10) exhibited monotropic (metastable) smectic A phase. The enantiotropic smectic A phase was observed from n-dodecyloxy derivatives onward to the last homologous synthesized.

• Periodical: Applied Mechanics and Materials (Volume 699)
• Pages: 233-238
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.699.233
• Online since: November 2014
• Authors: Kok Leei Foo, Sie Tiong Ha*
• Keywords: Benzothiazole, Liquid Crystals, Nematic, Schiff Base, Smectic A

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