Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Liquid Crystalline Properties of Schiff Base Mono- and Dimesogenic Compounds

Schiff Base 단일- 및 이메소제닉화합물의 액정성

  • 박주훈 (호서대학교 자연과학부) ;
  • 최옥병 (호서대학교 자연과학부) ;
  • 이진석 (호서대학교 자연과학부) ;
  • 강근명 (호서대학교 자연과학부) ;
  • 신주철 (호서대학교 자연과학부) ;
  • 김기환 (호서대학교 자연과학부) ;
  • 김학진 (한남대학교 자연과학부) ;
  • 이창준 (한남대학교 자연과학부) ;
  • 소봉근 (한남대학교 자연과학부) ;
  • 이수민 (한남대학교 자연과학부)
  • Received : 2004.08.10
  • Accepted : 2004.10.07
  • Published : 2005.02.28
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Abstract

The liquid crystalline properties of a series of main chain liquid crystalline polymers and four series compounds consisting of aromatic type Schiff base mesogenic units and polymethylene flexible spacers were studied. The thermal and liquid crystalline properties were investigated by differential scanning calorimetry and on the hot stage of a polarizing microscope. The nature of the liquid crystalline phase of the polymers and compounds depended greatly on the length of the central polymethylene spacer and on the terminal alkoxy groups. Polymers I and Series III exhibited an even-odd effect in melting and isotropization temperatures but Series II and Series IV exhibited an even-odd effect in isotropization temperatures. They formed nematic and smectic mesophases in melts as judged by their optical textures observed through a polarizing microscope.

방향족 Schiff base 메소제닉 단위와 폴리메틸렌 유연격자로 이루어진 한 계열의 주사슬 액정중합체와 네 계열 화합물의 액정성을 살펴보았다. 이들의 열적 성질과 액정성은 시차 주사 열분석기와 가열판이 부착된 편광현미경에 의하여 조사하였다. 중합체와 화합물 액정상의 성질은 중앙 폴리메틸렌 유연격자와 말단 알콕시기의 길이에 크게 의존하였다. 중합체 I과 계열 III 화합물은 녹는점과 등방성액체화 전이온도에서 짝수-홀수 효과를 보여 주었으나 계열 II와 IV 화합물은 등방성액체화 전이온도에서만 짝수-홀수 효과를 나타내었다. 편광현미경을 통하여 이들의 광학구조를 관찰하였을 때 네마틱과 스멕틱 액정상을 형성하였다.

Keywords

Acknowledgement

Supported by : 호서대학교

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