Silica: excellent chemical resistance , weatherproof


Silica (SiO2) is one of the most important rock-forming minerals. It is to be found in magmatic, metamorphous as well as sedimentary rocks and deposits. Basically SiO2 appears in nature as trigonal silica. For industrial use, mighty, workable silica sand deposits are of decisive importance. Nevertheless, chemical purity and constancy are not enough in order to apply silica directly as a raw material. In our plants silica sands are thoroughly prepared. The raw material has to pass extensive cleaning-, classification-, drying- and iron-free grinding processes in order to produce silica sands, flours and powders. For the production of silica flours and –powders with a defined grain size distribution separation processes are required in addition to iron-free grinding. We are able to produce silica powders with grain sizes down to 1 µm due to a fine-tuned combination of grind- and classification technology. Another refining step is the surface-treatment with silanes or silan-based substances which can be adjusted to the respective application.

 

Features

  • hardness 7 (Mohs)
  • density 2.65 g/cm³
  • high chemical resistance
  • low thermal expansion: 14*10-6/K (at T 20-300°C)
  • good electrical insulating properties (low tan delta)

 

Key applications:

  • paints, external plasters, anticorrosive coatings
  • epoxy resin for electrical applications
  • construction / construction chemicals
  • engineered stone
  • silicone

 

High Performance Fillers based on silica:
MILLISIL® / SILBOND® / SIKRON® / SILMIKRON®