The influence of alumino-silicate matrix composition on surface hydrophobic properties

Authors

  • Ljiljana M. Kljajević Department of Materials Science, Vinča Institute of Nuclear Sciences, University of Belgrade
  • Zuzana Melichova Faculty of Natural Sciences, Matej Bel University
  • Danilo D. Kisić Laboratory for Atomic Physics, Vinča Institute of Nuclear Sciences, University of Belgrade
  • Miloš T. Nenadović Laboratory for Atomic Physics, Vinča Institute of Nuclear Sciences, University of Belgrade
  • Bratislav Ž. Todorović Faculty of Technology of Leskovac, University of Niš
  • Vladimir B. Pavlović Institute of Technical Sciences of the Serbian Academy of Sciences and Arts
  • Snežana S. Nenadović Department of Materials Science, Vinča Institute of Nuclear Sciences, University of Belgrade

Abstract

The purpose of this investigation is to investigate the hydrophobicity of geopolymers, new alumino-silicate materials and the influence of Si/Al ratio on their surface properties. Contact angle measurement (CAM) as reliable indicator of hydrophobicity was determined for synthesized geopolymers using water and ethylene-glycol as reference liquids. Geopolymers were synthesized from various precursors: kaolin, bentonite and diatomite. Characterization of phase structure and microstructure was performed by XRD, FTIR, SEM/EDX methods. Contact angle measurements confirmed that the geopolymers synthesized from metakaolin are the most porous, which can be explained by the smallest Si/Al ratio. The maximum value of contact angle and free surface energy (110.2 mJ/m2) has been achieved for geopolymer synthesized by diatoms (GPMD). SEM micrograph of GPMD shows a homogeneous surface with some longitudinal cavities in the gel and is significantly different from the micrographs of other two geopolymer samples, GPMB and GPMK.

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Published

2019-04-01

Issue

Vol. 51 No. 2 (2019)

Section

Articles