Effect of the Addition of Si and Alkali Metal on the Viscosity and Molecular Behavior of Water Glass

Si와 알칼리 금속의 첨가에 따른 물유리의 점도 및 분자결합구조 특성변화

  • Ryu, Young Bok (Green Materials & Process Group, Korea Institute of Industrial Technology (KITECH)) ;
  • Lee, Man Sig (Green Materials & Process Group, Korea Institute of Industrial Technology (KITECH))
  • 류영복 (한국생산기술연구원 친환경재료공정그룹) ;
  • 이만식 (한국생산기술연구원 친환경재료공정그룹)
  • Received : 2017.12.04
  • Accepted : 2017.12.24
  • Published : 2018.02.10


In this study, the mixing characteristics of water glass and additives (Si, alkali metal), which are one of the main raw materials of silicate based binder used in the production of molds during casting process, were examined. Molecular structures of water glass, additives and mixtures were analyzed FT-IR and viscosity measurements and their correlation were compared. The addition of Si source to the water glass accelerated the Si networking in the material and increased the viscosity. When the alkali metal was added, the viscosity of the water glass decreased by suppressing the Si networking of the water glass. Viscosities of the water glass and lithium silicate (LS) mixtures increased when the content of LS was less than 20 wt% and gradually decreased when the content was more than 20 wt%. By adding KOH to the water glass, the viscosity could be lowered and it could be used effectively to mix with colloidal silica (CS) or potassium methyl siliconate (PMS).


water glass;FT-IR;viscosity;alkali metals;silicon (Si)


Supported by : 산업통상자원부, 한국생산기술연구원


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