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Synthesis and Characterization of Cellular SiO2 Materials by Foaming Sol Gels

Published online by Cambridge University Press:  21 February 2011

Josephine Covino
Affiliation:
Research Department, Naval Weapons, Center China Lake, Ca. 93555-6001
Allen P. Gehris Jr
Affiliation:
Research Department, Naval Weapons, Center China Lake, Ca. 93555-6001
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Abstract

A variety of cellular SiO2 materials have been synthesized using a foaming sol-gel process and their properties have been characterized. The process uses the rapid viscosity change during gelation to stabilize the structure of a foamed silica sol. It was found that the properties of these cellular materials are determined by method used. For example, the porosity and strength of these porous oxides depend on method of agitation and addition of Freon during the foaming process.

Density measurements, viscosity measurements as a function of pH, optical characterization, x-ray crystallography, ultimate compressive strength, dielectric constant measurements and thermal diffusivity were used to characterize these porous SiO2 materials. This paper will discuss the synthetic processes used to develop the porous silicas and properties of these materials.

Type
Research Article
Copyright
Copyright © Materials Research Society 1991

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