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소수성 증진을 위한 PMHS 유액 혼입 시멘트 복합체의 미세구조 분석

Microstructure Analysis of Cement Composite containing PMHS Emulsion to Improve Hydrophobic

  • 김영환 (경상국립대학교 토목공학과) ;
  • 오홍섭 (경상국립대학교 토목공학과)
  • 투고 : 2020.11.25
  • 심사 : 2021.02.25
  • 발행 : 2021.02.28

초록

고내구성 친환경 콘크리트를 개발하기 위하여 폴리메틸 하이드로실록산과 폴리비닐알코올을 교반, 혼합하여 발수 및 소수성화합물을 제조하였다. 시멘트페이스트에 혼합물을 첨가한 후 BSE와 EDS 분석을 통하여 수화반응 특성과 화학조성의 변화 정도를 분석하였으며, MIP 분석에 의해 미세공극을 평가하였다. PMHS 유액을 혼입한 시멘트는 수화반응성이 높아지고 모세공극률이 낮아지는 것으로 분석되었으나, 시멘트 페이스트내에서의 유액의 분산 정도에 따라 공극률의 편차가 발생하는 것으로 나타났다. 메타카올린을 혼입한 유액의 경우에는 PMHS 유액만을 사용한 경우와 수화도와 공극률에서 거의 차이가 없는 것으로 나타났다. 그러나 시멘트 표면을 PMHS 유액으로 도포한 경우의 접촉각은 OPC와 비교하여 크게 증가하는 것으로 나타났으며, 특히 PVA 섬유를 같이 사용한 경우에는 과소수성 표면으로 변화되는 것으로 분석되었다.

For developing the durable eco-concrete, water-repellent and hydrophobic emulsion were prepared by stirring and mixing polymethyl hydrosiloxane and polyvinyl alcohol. After adding the PMHS emulsion cement paste, the hydration reaction characteristics and the change in chemical composition were analyzed through BSE and EDS analysis, and the micropores were evaluated by MIP test. Cement mixed with PMHS emulsion was analyzed to increase the hydration reactivity and to decrease the capillary porosity, but it was found that the capillary porosity varies depending on the degree of dispersion of the emulsion in the cement paste. In the case of the emulsion containing metakaolin, there was little difference in hydration degree and porosity from the case of using only the PMHS emulsion. However, when the cement surface was coated with PMHS emulsion, the contact angle was found to increase significantly compared to OPC, and it was analyzed that especially when PVA fiber was used together, it changed to a hypohydrophobic surface.

키워드

참고문헌

  1. Almusallam, A. A., Khan, F. M., Dulaijan, S. U., and Al-Amoudi, O. S. B. (2003), Effectiveness of surface coatings in improving concrete durability, Cement and concrete composites, 25(4-5), 473-481. https://doi.org/10.1016/S0958-9465(02)00087-2
  2. Dai, J. G., Akira, Y., Wittmann, F. H., Yokota, H., and Zhang, P. (2010), Water repellent surface impregnation for extension of service life of reinforced concrete structures in marine environments: the role of cracks, Cement and Concrete Composites, 32(2), 101-109. https://doi.org/10.1016/j.cemconcomp.2009.11.001
  3. Flores-Vivian, I., Hejazi, V., Kozhukhova, M. I., Nosonovsky, M., and Sobolev, K. (2013), Self-assembling particle-siloxane coatings for superhydrophobic concrete, ACS applied materials &interfaces, 5(24), 13284-13294. https://doi.org/10.1021/am404272v
  4. Lee, H, Oh H., Sim J., and Zi G. (2013), An Experimental Study on the Multi-Deterioration Resistances of Concrete containing Waste-glass Sludge, Journal of KOSHAM, 13(2),067-074
  5. Medeiros, M., and Helene, P. (2008), Efficacy of surface hydrophobic agents in reducing water and chloride ion penetration in concrete, Materials and Structures, 41(1), 59-71. https://doi.org/10.1617/s11527-006-9218-5
  6. Muzenski, S., Flores-Vivian, I., & Sobolev, K. (2015), Hydrophobic engineered cementitious composites for highway applications, Cement and Concrete Composites, 57, 68-74. https://doi.org/10.1016/j.cemconcomp.2014.12.009
  7. Oh, H. (2018), A Study on the Fundamental Mechanical Properties of Hydrophobic Cementeous Mortar using Silane Admixtures, Journal of the Korean Recycled Construction Resources Institute, 6(2), 79-86. https://doi.org/10.14190/JRCR.2018.6.2.79
  8. Park, M., Noh, J., & Lee, B. (2019), Porosity and Abrasion Resistance of Concrete Coated by Surface enhanced type Water Repellent, Journal of the Korea Institute for Structural Maintenance and Inspection, 23(4), 31-36.
  9. Ramachandran, R., Sobolev, K., and Nosonovsky, M. (2015), Dynamics of droplet impact on hydrophobic/icephobic concrete with the potential for superhydrophobicity, Langmuir, 31(4), 1437-1444. https://doi.org/10.1021/la504626f
  10. Ramachandran, R., Kozhukhova, M., Sobolev, K., & Nosonovsky, M. (2016), Anti-icing superhydrophobic surfaces: Controlling entropic molecular interactions to design novel icephobic concrete, Entropy, 18(4), 132. https://doi.org/10.3390/e18040132
  11. Sobolev, K., Nosonovsky, M., Krupenkin, T., Flores-Vivian, I., Rao, S., Kozhukhova, M., ... & Rivero, R. (2013), Anti-icing and de-icing superhydrophobic concrete to improve the safety on critical elements on roadway pavements (No. CFIRE 07-03), National Center for Freight and Infrastructure Research and Education (US).
  12. Wong, H. S., Barakat, R., Alhilali, A., Saleh, M., and Cheeseman, C. R. (2015), Hydrophobic concrete using waste paper sludge ash, Cement and Concrete Research, 70, 9-20. https://doi.org/10.1016/j.cemconres.2015.01.005