Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-25T15:34:38.187Z Has data issue: false hasContentIssue false

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
Get access

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Hengst, R.R. and Tressler, R.E., Cement Concrete Res. 13, pg.127 (1983).CrossRefGoogle Scholar
2. Morgan, J.S., Wood, J.L. and Bradt, R.C., Mater. Sci. Eng. 47., pg. 37 (1981).CrossRefGoogle Scholar
3. Verwell, H., Dewith, G. and Veeneman, D., J. Mater. Sci. Eng. 20, pg. 1069 (1985).Google Scholar
4. Lange, F.F. and Miller, K. T., Adv. Ceram. Mater. 2, pg. 827 (1987).CrossRefGoogle Scholar
5. Fujiu, T., Messing, G. L. and Huebner, W., J. Am. Ceram. Soc. 73 (1), pg. 85 (1990).CrossRefGoogle Scholar
6. Brown, A.G., Thuman, W.C., and McBain, J.W.. J. Colloid Sci. 8, pg. 491 (1953).CrossRefGoogle Scholar
7. ASTM C373-72 (Reapproved 1982). “Standard Test Method for Water Absorption, Bulk Density, Apparent Porosity, and Apparent Specific Gravity of Fired Whiteware Products.”Google Scholar
8. ASTM C 773–8, 1988. “Standard Test Method for Compressive (Crushing) Strength of Fired Whiteware Materials.”Google Scholar
9. Touloukian, Y.S., Powell, R.W., Ho, C.Y. and Niolaou, M.C., “Thermal Diffusivity” in Thermophysical Properties of Matter, 10, pp. 15a37a. (IFI/Plenum, New York 1973).Google Scholar
10. Kobayaski, K., “Simultaneous Measurement of Thermal Diffusivity and Specific Heat at High Temperatures by a Single Rectangular Pulse Heating Method,” International Journal of Thermophysics 7, 181195 (1986).CrossRefGoogle Scholar
11. Wong-Ng, W., McMurdie, H., Paretzkin, B., Hubbard, C., Dragoo, A., National Bureau of Standards (USA), JCPDS Grant-in-Aid Report, (1988); JCPDS #39–1425.Google Scholar
12. Sato, Mineral J. (Japan) 4, pg. 215; Dana's System of Mineralology, 7th Ed., 273, (1962); JCPDS #18–1170.Google Scholar
13 Wu, M., Fujiu, T. and Messing, G.L., J. of Non-Crystalline Solids 1–3, pg. 407, (1990).CrossRefGoogle Scholar
14. Covino, J. and Nissan, R.A., “Better Ceramic Through Chemistry” Mat. Res. Soc. Symp. Proc. 73, pg. 565, (1986).CrossRefGoogle Scholar