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막유화법을 이용한 단분산성 실리카-루비덤® 마이크로 입자의 제조 및 잠열 특성

Preparation of Monodispersed Silica-Rubitherm®Microparticles Using Membrane Emulsification and Their Latent Heat Properties

  • 김수연 (충북대학교 공업화학과) ;
  • 정연석 (충북대학교 공업화학과) ;
  • 이선호 (충북대학교 공업화학과) ;
  • 유진오 (충북대학교 공업화학과) ;
  • 염경호 (충북대학교 공업화학과)
  • Kim, Soo-Yeon (Department of Engineering Chemistry, College of Engineering, Chungbuk National University) ;
  • Jung, Yeon-Seok (Department of Engineering Chemistry, College of Engineering, Chungbuk National University) ;
  • Lee, Sun-Ho (Department of Engineering Chemistry, College of Engineering, Chungbuk National University) ;
  • You, Jin-Oh (Department of Engineering Chemistry, College of Engineering, Chungbuk National University) ;
  • Youm, Kyung-Ho (Department of Engineering Chemistry, College of Engineering, Chungbuk National University)
  • 투고 : 2015.05.02
  • 심사 : 2015.05.20
  • 발행 : 2015.06.30

초록

최근들어 에너지 고갈로 인해 에너지 저장 및 대체 에너지에 대한 관심이 점차 높아 지고 있다. 이로 인해 상변화 물질을 이용한 에너지 저장 및 이동에 대한 연구가 활발히 진행 되고 있다. 본 연구에서는 SPG막(Shirasu porous glass membrane)을 통한 막유화법을 이용하여 상변화 물질인 파라핀계 루비덤$^{(R)}$ (RT-21과 RT-24)을 분산상으로 하여 단분산성 마이크로 입자를 제조하고, 외부를 실리카로 코팅하여 열정 안정성을 향상시키고 열적 특성을 조사하였다. 단분산성 루비덤$^{(R)}$ 입자의 제조를 위해 분산상 압력, 유화제 농도, 루비덤$^{(R)}$과 실리카의 비율을 변수로 하여 평균 입자 크기 $7-8{\mu}m$를 얻었다. Differential scanning calorimetry (DSC)와 Thermogravimetry analysis (TGA)를 이용하여 열적 안정성과 잠열 등의 열적 특성을 조사하였고, Particle size analyzer (PSA), Scanning electron microscopy(SEM), optical microscopy를 이용하여 입자 분포와 캡슐화 유무를 확인하였다. 또한, Fourier transform infrared spectroscopy (FT-IR)를 통하여 정성분석을 시행하였다. 결과적으로, 막유화법을 이용하여 얻은 실리카 코팅된 단분산성 루비덤$^{(R)}$ 입자는 향상된 열적 안정성을 보였으며, 순수한 루비덤$^{(R)}$의 80% 이상의 잠열을 유지하는 것을 보여 기존의 상변화 물질의 상안정성을 보완하여 열저장성 기능성 벽지와 건축물, 인테리어 제품에 사용 가능함을 알 수 있었다.

Recently, the importance of energy saving and alternative energy is significantly increasing due to energy depletion and the phase change material (PCM) research for saving energy is also actively investigating. In this research, the membrane emulsification using SPG membrane was used to make various microencapsulated phase change material (MPCM) particles which were comprised of $Rubitherms^{(R)}$ (RT-21 and RT-24) core and silica coating. We investigated the pressure of the dispersion phase, the concentration of surfactant, and the ratio of $Rubitherm^{(R)}$ and silica to prepare various MPCM particles. The DSC and TGA were used to examine the heat stability and latent heat properties. Also, PSA, SEM, and optical microscopy were used to confirm the size of $Rubitherm^{(R)}$ particles and the thickness of silica shell. The average of particle size was $7-8{\mu}m$. And, FT-IR was also used to enforce the qualitative analysis. Finally, the MPCM particles obtained from membrane emulsification showed monodispersed size distribution and the heat stability and latent heat were kept up to 80% compared to pure $Rubitherm^{(R)}$. So, it can be effectively used for wallpaper, buildings and interior products for energy saving as PCMs.

키워드

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