Synthesis and Liquid Crystalline Properties of New Chiral Monomers and Polysiloxanes

Abstract:

To study the structure-property relationships of new chiral liquid crystalline materials based on menthol and explore their potential applications, a monomer 4-(4-allyloxybenzoyloxy) phenyl-4-menthyl-oxyacetyloxybiphenyl-4-carboxylate (LCM) and the corresponding homopolymer (LCP) were synthesized. The chemical structure was characterized by FT-IR and ¹H NMR. The liquid crystalline properties were investigated by differential scanning calorimetry, thermogravimetric analysis, polarizing optical microscopy, and X-ray diffraction. The monomer LCM formed a cholesteric phase when a flexible linkage chain was inserted between the mesogenic core and the terminal menthyl groups by reducing the steric effect. The homopolymer LCP exhibited a batonnet texture of a smectic A phase.

• Periodical: Advanced Materials Research (Volume 815)
• Pages: 747-751
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.815.747
• Online since: October 2013
• Authors: Jian She Hu, Yi Nan Liu, Ya Ting Song, Di Wang
• Keywords: Chiral, Cholesteric Phase, Liquid Crystalline, Menthol

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