Sodium Silicate Based Aerogels via Ambient Pressure Drying

  • A. Venkateswara Rao
  • G. M. Pajonk
  • Uzma K. H. Bangi
  • A. Parvathy Rao
  • Matthias M. Koebel
Chapter
Part of the Advances in Sol-Gel Derived Materials and Technologies book series (Adv.Sol-Gel Deriv. Materials Technol.)

Abstract

The first step in the preparation of silica aerogels is a sol–gel process producing a gel. This is followed by drying of the gel by either supercritical drying (SCD) or ambient pressure drying (APD). Traditionally, silica aerogels are prepared by the more energy-intensive and -expensive SCD method using alkoxide precursors such as tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS). This choice partly restricts the commercialization of aerogels. Recent developments have shown great potential of the APD as an alternative method employing sodium silicate (Na2SiO3) as a purely inorganic precursor. The properties of such aerogels are very similar to those obtained by more conventional methods. This chapter focuses on the preparation of sodium silicate based aerogels via APD and the effect of various parameters on their physicochemical properties. The process chemistry is further contrasted with factors relevant for large-scale production.

Keywords

Permeability Porosity Hydrolysis Dust Hexane 

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • A. Venkateswara Rao
    • 1
  • G. M. Pajonk
    • 2
  • Uzma K. H. Bangi
    • 1
  • A. Parvathy Rao
    • 1
  • Matthias M. Koebel
    • 3
  1. 1.Air Glass Laboratory, Department of PhysicsShivaji UniversityKolhapurIndia
  2. 2.Laboratoire des Matériaux et Procédés CatalytiquesUniversité Claude Bernard Lyon 1VilleurbanneFrance
  3. 3.Building Materials Group, Department of Building Science and TechnologyEmpa – Swiss Federal Laboratories for Materials Science and TechnologyDübendorfSwitzerland

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