DOI QR코드

DOI QR Code

Size Effect of Hollow Silica Nanoparticles as Paint Additives for Thermal Insulation

단열 페인트 첨가제로써 중공형 실리카 나노입자의 크기에 따른 효과

  • Kim, Jisue (Department of Chemical Engineering, Kwangwoon University) ;
  • Kim, Younghun (Department of Chemical Engineering, Kwangwoon University)
  • 김지수 (광운대학교 화학공학과) ;
  • 김영훈 (광운대학교 화학공학과)
  • Received : 2021.12.16
  • Accepted : 2022.02.15
  • Published : 2022.03.31

Abstract

Using air as an insulator due to its low heat transfer coefficient has been studied and has been widely commercialized to save energy in the field of thermal insulation technology. In this study, we analyzed the heat insulating effect of hollow silica nanoparticles mixed in non-uniform size, and the maximum heat insulating efficiency of these particles given the limited number of particles that can be mixed with a medium such as paint. The hollow silica nanoparticles were synthesized via a sol-gel process using a polystyrene template in order to produce an air layer inside of the particles. After synthesis, the particles were analyzed for their insulation effect according to the size of the air layer by adding 5 wt % of the particles to paint and investigating the thermal insulation performance by a heat transfer experiment. When mixing the particles with white paint, the insulation efficiency was 15% or higher. Furthermore, the large particles, which had a large internal air layer, showed a 5% higher insulation performance than the small particles. By observing the difference in the insulation effect according to the internal air layer size of hollow silica nanoparticles, this research suggests that when using hollow particles as a paint additive, the particle size needs to be considered in order to maximize the air layer in the paint.

에너지 절약을 위한 연구 중 단열 기술 분야에서는 공기의 낮은 열전도도를 활용한 연구가 이뤄지고 있으며 널리 상용화 되고 있다. 본 연구에서는 입자 내부에 공기층을 갖는 중공형(hollow) 형태의 실리카 나노 입자를 제조하여 공기층 크기가 단열 성능에 미치는 영향에 대해 고찰하였다. Polystyrene 주형법을 이용하여 졸-겔공정을 통해 속이 빈 중공형 실리카 나노 입자(Hollow silica nanoparticles)를 제조하였고, 입자를 5 wt %로 도료에 첨가한 후 열전달 실험을 통해 단열 성능을 확인하였다. 기존 페인트에 입자를 혼합하여 약 15 %이상의 단열효율을 나타냈으며, 내부 공기층의 크기가 큰 입자가 작은 입자에 비해 5% 높은 단열 성능을 나타냈다. 이번 연구를 통해 내부 크기에 따른 단열효과의 차이를 보여줌으로써, 중공형 형태의 입자를 첨가제나 도료 제조에 사용하는 경우 단열효과를 높이기 위해 매질 내에서 입자가 공기층을 최대로 이룰 수 있도록 입자의 크기를 고려해야함을 제시한다.

Keywords

References

  1. Al-Homoud, M.S., "Performance characteristics and practical applications of common building thermal insulation materials," Build. Environ., 40, 353-366 (2005). https://doi.org/10.1016/j.buildenv.2004.05.013
  2. Li, T., Huang, F., Zhu, J., Tang, J., and Liu, J., "Effect of foaming gas and cement type on the thermal conductivity of foamed concrete," Constr. Build. Mater., 231, 117197 (2020). https://doi.org/10.1016/j.conbuildmat.2019.117197
  3. Hu, F., An, L., Li, C., Liu, J., Ma, G., Hu, Y., Huang, Y., Liu, Y., Thundat, T., and Ren, S., "Transparent and Flexible Thermal Insulation Window Material," Cell Rep. Phys. Sci., 1, 100140 (2020). https://doi.org/10.1016/j.xcrp.2020.100140
  4. Zhang, Z., Wang, K., Mo, B., Li, X., and Cui, X., "Preparation and characterization of a reflective and heat insulative coating based on geopolymers," Energy Build., 87, 220-225 (2015). https://doi.org/10.1016/j.enbuild.2014.11.028
  5. Tao, D., Li, X., Dong, Y., Zhu, Y., Yuan, Y., Ni, Q., Fu, Y., and Fu, S., "Super-low thermal conductivity fibrous nanocomposite membrane of hollow silica/polyacrylonitrile," Compos. Sci. Technol., 188, 107992 (2020). https://doi.org/10.1016/j.compscitech.2020.107992
  6. Long, J., Jiang, C., Zhu, J., Song, Q., and Hu, J., "Controlled TiO2 coating on hollow glass microspheres and their reflective thermal insulation properties," Particuology, 49, 33-39 (2020). https://doi.org/10.1016/j.partic.2019.03.002
  7. Grandcolas, M., Jasinski, E., Gao, T., and Jelle, B. P., "Preparation of low density organosilica monoliths containing hollow silica nanospheres as thermal insulation materials," Mater. Lett., 250, 151-154 (2019). https://doi.org/10.1016/j.matlet.2019.05.021
  8. Li, B., Yuan, J., An, Z., and Zhang, J., "Effect of microstructure and physical parameters of hollow glass microsphere on insulation performance," Mater. Lett., 65, 1992-1994 (2011). https://doi.org/10.1016/j.matlet.2011.03.062
  9. Ifijen, I.H., and Ikhuoria, E.U., "Monodisperse Polystyrene Microspheres: Studies on the Effects of Reaction Parameters on Particle Diameter and Colloidal Stability," Tanzania J. Science., 46, 19-30 (2020).
  10. Hong, J., Han, H., Hong, C.K., and Shim, S.E., "A direct preparation of silica shell on polystyrene microspheres prepared by dispersion polymerization with polyvinylpyrrolidone", J. Polym. Sci. A: Polym. Chem., 46, 2884-2890 (2008). https://doi.org/10.1002/pola.22624
  11. Mofid, S.A., Jelle, B.P., Zhao, X., Gao, T., Grandcolas, M., Cunningham, B., Ng, S., and Yang, R., "Utilization of size-tunable hollow silica nanospheres for building thermal insulation applications," J. Build. Eng., 31, 101336 (2020). https://doi.org/10.1016/j.jobe.2020.101336
  12. Hu, F., Wu, S., and Sun, Y., "Hollow-Structured Materials for Thermal Insulation," Adv. Mater., 31, 1801001 (2019). https://doi.org/10.1002/adma.201801001