Polymer(Korea) (폴리머)

The Polymer Society of Korea (한국고분자학회)
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Induction Mechanism of Planar Arrangement in Cholesteric Liquid Crystals

콜레스테릭 액정의 Planar 배열 유도 메카니즘

  • Jung, Gap-Ha (Materials Research Center for Information Display, Kyung Hee University) ;
  • Lee, Mong-Ryong (Materials Research Center for Information Display, Kyung Hee University) ;
  • Seo, In-Seon (Materials Research Center for Information Display, Kyung Hee University) ;
  • Song, Ki-Gook (Materials Research Center for Information Display, Kyung Hee University)
  • 정갑하 (경희대학교 영상정보소재기술 연구센터) ;
  • 이몽룡 (경희대학교 영상정보소재기술 연구센터) ;
  • 서인선 (경희대학교 영상정보소재기술 연구센터) ;
  • 송기국 (경희대학교 영상정보소재기술 연구센터)
  • Received : 2011.02.16
  • Accepted : 2011.03.30
  • Published : 2011.05.25
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Abstract

The induction mechanisms of planar arrangements in cholesteric liquid crystals (CLC) which showed selective reflections of visible light were investigated by measuring the selective reflectivity and FTIR peak intensity of $C{\equiv}N$ stretching band. Although the planar arrangement of CLC was not as perfectly induced as the cases prepared with using alignment layers, it could be also induced by stretching polymer substrate or by applying shear forces. The planar arrangements were induced by forming CLC helical structures on top of liquid crystal molecules which were in contact with the substrate and oriented all in the same direction.

선택 반사를 보여주는 콜레스테릭 액정의(cholesteric liquid crystal; CLC) planar 배열이 유도되는 메카니즘을 CLC 셀의 선택 반사율과 FTIR $C{\equiv}N$ 피크 세기를 측정하여 조사하였다. 배향막을 사용한 경우보다는 planar 배열 유도가 완전하지는 않았지만 shear force를 이용하거나 또는 고분자 기판을 연신하여 배향막을 사용하지 않은 상태에서 planar 배열을 유도하였다. CLC의 planar 배열이 유도되는 메카니즘은 기판 표면에 접촉하는 액정분자들이 한 방향으로 늘어서면, 그 액정분자 위에 CLC의 나선 구조들이 기판에 수직으로 형성되며 planar 배열이 유도되는 것이다.

Keywords

References

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