Elastomers and Composites

The Rubber Society of Korea (한국고무학회)
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Synthesis and Properties of Semi-flexible Liquid Crystalline Polyesters with Rigid Lateral Group

강직한 측쇄기를 갖는 반 유연성 액정폴리에스터의 합성 및 성질

  • Park, Jong-Ryul (Division of Advanced Materials Science and Engineering, Kongju National University) ;
  • Lee, Eung-Jae (Dept. of Bioenvironmental & Chemical Engineering, Chosun College University of Science & Technology) ;
  • Yoon, Doo-Soo (Dept. of Bioenvironmental & Chemical Engineering, Chosun College University of Science & Technology) ;
  • Bang, Moon-Soo (Division of Advanced Materials Science and Engineering, Kongju National University) ;
  • Choi, Jae-Kon (Dept. of Biochemical & Polymer Engineering, Chosun University)
  • 박종률 (공주대학교 신소재공학부) ;
  • 이응재 (조선이공대학교 생명환경화공과) ;
  • 윤두수 (조선이공대학교 생명환경화공과) ;
  • 방문수 (공주대학교 신소재공학부) ;
  • 최재곤 (조선대학교 생명화학고분자공학과)
  • Received : 2013.11.06
  • Accepted : 2013.11.18
  • Published : 2013.12.31
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Abstract

A series of liquid crystalline polyesters containing the 4-chloro benzoate group on the hydroquinone unit of rigid group were synthesized through solution polymerization of 2,5-di(4-chlorobenzoate)hydroquinones and 4,4'-dicarboxy-${\alpha},{\omega}$-diphenoxy alkane. The structure and properties for synthesized polymers were investigated by $^1H$-NMR, FT-IR, DSC, TGA, and POM. As result of investigations, The presence of the methylene group and bulky lateral groups in polymer chain have a great influence on the properties of polymers such as solubilities and thermal transitions. The optical textures of polymers revealed a weak birefringence in the melt and indicated that they form nematic mesophase. All polymers have very narrow mesophase temperature ranges.

주 사슬의 강직그룹의 하이드로퀴논 단위에 4-클로로벤조에이트기가 결합된 액정폴리에스터가 단위체인 2,5-다이(4-클로로벤조에이트)하이드로퀴논과 4,4'-디카복시-${\alpha},{\omega}$-디페녹시 알케인의 용액중합에 의하여 합성되었다. 합성된 중합체의 구조와 성질은 $^1H$-NMR, FT-IR, DSC, TGA, POM에 의하여 조사되었다. 조사의 결과에 의하면, 중합체 사슬의 메틸렌기와 벌키한 치환기는 용해도나 열전이와 같은 성질에 큰 영향을 미쳤으며, 모든 중합체들은 편광현미경 관찰에서 약한 복굴절 현상을 갖는 네마틱 액정상의 texture를 나타내었고, 매우 좁은 액정상 온도구간을 나타내었다.

Keywords

References

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