Synthesis and Characterization of New Main Chain Liquid Crystalline Coumarin Compound with Ester Moiety

Ester기를 갖는 새로운 주쇄형 액정 coumarin 화합물의 합성 및 특성분석

  • Lee, Jong-Back (Department of Chemical Engineering, Dongeui University) ;
  • Kang, Byung-Chul (Department of Chemical Engineering, Dongeui University) ;
  • Lee, Gang-Choon (Department of Chemical Engineering, Dongeui University) ;
  • Lee, Dong-Jin (Korea Institute of Ceramic Engineering & Technology) ;
  • Hideyuki, Kihara (Nanotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST))
  • Published : 2009.12.31


4-(6-bromohexyloxy)benzoic acid was synthesized from benzyl 4-Hydroxybenzoate and 1,6-dibromohexane. It was reacted with hydroquinone to obtain a new mesogenic ester having an bromine group. One kind of new photoresponsive coumarin compound was prepared by the reaction of mesogenic ester with coumarin sensitive to the ultraviolet. Structures of the compound were identified by FT-IR and $^1H$-NMR spectroscopies. Their phase transition temperatures and thermal stability were also investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and x-ray diffraction analysis. From optical polarizing microscopy, the prepared compound was found to show enantiotropic liquid crystallinity with smectic and nematic textures.


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