에폭시계 고분자 분산형 액정의 경화반응과 상거동

Cure Reaction and Phase Behavior of Epoxy-Based Polymer Dispersed Liquid Crystals

  • 이규재 (금오공과대학교 고분자공학과) ;
  • 박원호 (충남대학교 공과대학 섬유공학과) ;
  • 조동환 (금오공과대학교 고분자공학과) ;
  • 방대석 (금오공과대학교 고분자공학과) ;
  • 이상철 (금오공과대학교 고분자공학과)
  • 발행 : 2003.12.01

초록

In an epoxy resin/polymer dispersed liquid crystal (PDLC) system, the effect of PDLC content (0-40 wt%) has been investigated under dynamic and isothermal curing conditions. In the dynamic curing reaction, the reaction rate of epoxy resin decreased as the PDLC content increased. In the isothermal curing reaction, the reaction rate of epoxy resin decreased as the PDLC content increased or as the curing temperature decreased. This was caused by the inhibition effect of PDLC on the curing reaction of epoxy resin. In addition, the distribution and morphology of PDLC in the cured epoxy/PDLC system have been investigated using differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Above 30 wt% PDLC content, the pattern of DSC peak was changed due to the enthalpy obtained during the phase separation. This has been confirmed by measuring the time required for phase separation. From SEM micrographs, the most uniform and smallest size of PDLC in the cured epoxy/PDLC system was obtained at the PDLC content of 30 wt%.

키워드

참고문헌

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