Elastomers and Composites

  • 제44권4호
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  • Pages.416-422
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  • 2009
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  • 2092-9676(pISSN)
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  • 2288-7725(eISSN)
한국고무학회 (The Rubber Society of Korea)
권호 표지

Ester기를 갖는 새로운 주쇄형 액정 coumarin 화합물의 합성 및 특성분석

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

  • 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))
  • 발행 : 2009.12.31
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초록

Benzyl 4-Hydroxybenzoate와 1,6-Dibromohexane을 반응시켜 4-(6-bromohexyloxy)benzoic acid를 합성하였다. 이것을 하이드로퀴논과 반응시켜 브롬 그룹을 갖는 새로운 mesogenic ester를 합성하였다. Mesogenic ester를 자외선에 민감한 coumarin과 반응시켜 새로운 형태의 광응답성 coumarin 화합물을 합성 하였다. 합성된 화합물의 구조는 FT-IR 및 $^1H$-NMR에 의해 확인 하였으며, 그들의 열적 상전이온도 및 안정성들은 DSC, 편광현미경 및 X-선 회절에 의해 조사 하였다. 한편 합성된 새로운 화합물은 광학 편광 현미경 관찰에 의해 스멕틱 및 네마틱 구조를 갖는 쌍방성 액정성을 보였다.

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.

키워드

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