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Elastical Properties of Aerogels -a Sensitive Monitor of Structural Changes

  • J. Groß
  • J. Lukas
  • J. Fricke
  • F. Schwertfeger
Chapter

Abstract

We present two examples of tiny changes in the microstructure of silica aerogels. Firstly, the elastic modulus of supposedly identical samples dried in autoclaves of different volumes were examined. A higher elastic modulus resulted from drying in a smaller vessel. This was caused by a slightly larger amount of water relative to the methanol content of the vessel, introduced with the samples. Secondly, the change of elastic modulus, mass and linear dimension of heat treated aerogel samples was measured. After heat treatment an elastical relaxation was observed that can be explained by chemisorption of water molecules.

Keywords

Elastic Modulus Sound Velocity Silica Aerogel Follow Heat Treatment Ultrasonic Absorption 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • J. Groß
    • 1
  • J. Lukas
    • 1
  • J. Fricke
    • 1
  • F. Schwertfeger
    • 2
  1. 1.Physikalisches InstitutWürzburgGermany
  2. 2.Institut für Anorganische ChemieUniversität WürzburgWürzburgGermany

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