Interfacial Properties and Sensing of Carbon Nanofiber/Tube and Electrospun Nanofiber/Epoxy Composites Using Electrical Resistance Measurement and Micromechanical Technique

전기저항측정 및 미세역학시험법을 이용한 탄소나노섬유/튜브 및 전기방사된 나노섬유/에폭시 복합재료의 계면특성 및 감지능 연구

  • 정진규 (경상대학교 신소재공학부/고분자공학전공) ;
  • 김성주 (경상대학교 신소재공학부/고분자공학전공) ;
  • 박종만 (경상대학교 신소재공학부/고분자공학전공)
  • Published : 2005.08.01

Abstract

Nondestructive damage sensing and load transfer mechanisms of carbon nanotube (CNT) and nanofiber (CNF)/epoxy composites have been investigated by using electro-micromechanical technique. The electrospun PVDF nanofibers were also prepared as a piezoelectric sensor. The electro-micromechanical techniques were applied to evaluate sensing response of carbon nanocomposites by measuring electrical resistance under an uniform cyclic loading. Composites with higher volume content of CNT showed significantly higher tensile properties than neat and low volume$\%$ CNT composites. CNT composites showed humidity sensing within limited temperature range. CNT composites with smaller aspect ratio showed higher apparent modulus due to high volume content in case of shorter aspect ratio. Thermal treated electrospun PVDF nanofiber showed higher mechanical properties than the untreated case due to crystallinity increase, whereas load sensing decreased in heat treated case. Electrospun PVDF nanofiber web also showed sensing effect on humidity and temperature as well as stress transferring. Nanocomposites and electrospun PVDF nanofiber web can be applicable for sensing application.

탄소나노튜브 및 탄소나노섬유/에폭시 복합재료의 비파괴 손상감지능 및 응력전달 메카니즘이 전기-미세기계적 실험법을 통하여 조사되었다. 전기-미세기계적 실험법은 균일한 반복하중 하에서 전기저항을 측정함으로써 탄소나노복합재료의 감지반응을 평가하는 것이다. 큰 탄소섬유 부피 분율이 있는 복합재료가 에폭시 자체나 작은 부피 분율에 비하여 매우 큰 인장강도 특성을 보여주었다. 탄소나노섬유 복합재료는 제한된 온도범위 내에서 습도 감지능을 보여주었다. 형상비가 작은 탄소나노섬유 복합재료는 많이 첨가된 부피량에 기인하여 보다 큰 겉보기 탄성계수를 보여 주었다. 열처리된 전기 방사된 PVDF 나노섬유는 증대된 결정화에 기인하여 미처리의 경우보다 큰 기계적 특성을 보여 주었으며, 그 반면에 응력 감지능은 열처리의 경우에 감소를 보여 주었다. 전기 방사된 나노섬유는 또한 응력전달 뿐만 아니라 습도 및 온도에 대한 감지능도 나타내었다. 탄소나노튜브. 탄소나노섬유 및 전기 방사된 PVDF 나노섬유는 나노복합재료의 다기능에 응용할 수 있을 것이다.

Keywords

References

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