Article
  • Effects of Methylene flexible Spacer on the Properties of Liquid Crystalline Polymer Containing Biphenylene Units
  • Yug GC, Kim CB, Choi SW, Kim WY
  • 메틸렌 유연쇄가 비페닐구조를 가지는 액정중합체의 성질에 미치는 영향
  • 육경창, 김종배, 최상원, 김완영
Abstract
Aromatic liquid crystalline polyesters were synthesized by solution polymerization from terephthalic acid/p, p'-biphenyl dicarboxylic acid(75/25 by mole%), hydroquinone(HQ) and a, ω-bis(4-hydroxy phenoxy)alkane(BIS-n) with various length of flexible spacers(n=6∼9). Effects of HQ/BIS-n ratio(by mole%) on the properties of polymers were investigated with DSC, TGA, cross-polarized microscopy, and X-ray diffractometer. The textures of polymers changed depending on the number of methylene units. The polymers with n=6 formed smectic phase, while those of n=7 showed nematic one. Transition temperatures of liquid crystalline polymers in this study showed typical oddeven effects. Thermal stabilities of polymers decreased with increase of BIS-n content.

p, p'-비페닐 디카르본산과 테레프탈산의 양이 1 : 3인 기본구조에 메틸렌의 수(n)가 6∼9인 α, ω-비스(4-히드록시 페녹시)알칸(BIS-n)을 가하여 용액중합법으로 액정 폴리에스테르를 제조하였다. 합성한 중합체의 유연쇄 도입에 따른 열적성질은 DSC, TGA로 조사하였고, 형성하는 액정상은 편광현미경으로 확인하였다. 액정상은 n에 따라 변하여 n이 6인 것은 스멕틱상을, n이 7인 것은 네마틱성을 나타내었고 합성한 중합체 Tm과 Ti는 뚜렷한 짝수-홀수 효과를 나타내었다. 또한 중합체의 열안정성은 중합체중의 Bis-n의 양이 증가할수록 저하되었다.

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  • Polymer(Korea) 폴리머
  • Frequency : Bimonthly(odd)
    ISSN 0379-153X(Print)
    ISSN 2234-8077(Online)
    Abbr. Polym. Korea
  • 2023 Impact Factor : 0.4
  • Indexed in SCIE

This Article

  • 1992; 16(3): 312-319

    Published online May 25, 1992