Composites Research

The Korean Society for Composite Materials (한국복합재료학회)
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Development of Highly Thermal Conductive Liquid Crystalline Epoxy Resins Bearing Phenylcyclohexyl Mesogenic Moieties

Phenylcyclohexyl mesogenic moieties를 함유한 고 열전도성 액정성 에폭시 수지의 개발

  • Jeong, Iseul (Carbon Composite Materials Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST)) ;
  • Kim, Youngsu (Carbon Composite Materials Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST)) ;
  • Goh, Munju (Carbon Composite Materials Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST))
  • Received : 2017.08.24
  • Accepted : 2017.12.29
  • Published : 2017.12.31
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Abstract

The new liquid crystalline (LC) epoxy was designed by substituting the phenylcyclohexyl (PCH) mesogen moiety with an alkyl chain at the 2,5 position of the diglycidyl terephthalate. The mesomorphic properties were evaluated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). All LC epoxy derivatives exhibited an enantiotropic smectic phase upon heating and cooling process. The LC phase temperature range was widened by mixing the eutectic mixture of LC epoxies. Interestingly, the cured LC epoxy exhibited the highest thermal conductivity of $0.4W{\cdot}m^{-1}{\cdot}K^{-1}$. The novel LC epoxy with high thermal conductivity might be used as a composite material for electronic and display devices.

Phenylcyclohexyl (PCH) mesogen을 diglycidyl terephthalate의 2,5 위치에 치환시킨 새로운 액정성 에폭시 수지를 설계하였다. 이 물질의 액정성은 DSC(differential scanning calorimetry)와 POM(polarized optical microscopy)으로 분석하였다. 모든 액정성 에폭시 유도체는 가열 및 냉각 시에 모두 smectic상을 나타내는 enantiotropic한 성질을 나타내었다. 액정성 에폭시의 공융 혼합물을 통하여 액정 온도구간을 확장시켰다. 경화된 신규 액정성 에폭시는 $0.4W{\cdot}m^{-1}{\cdot}K^{-1}$의 높은 열전도도를 나타냈다. 높은 열전도도를 갖는 신규 액정성 에폭시는 전자 및 디스플레이용 복합소재로 이용될 것으로 기대된다.

Keywords

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