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Preparation of Aryl-Bridged Polysilsesquioxane Aerogels

Published online by Cambridge University Press:  25 February 2011

Douglas A. Loy ,
Kenneth J. Shea  and
Edward M. Russick
Douglas A. Loy
Affiliation:
Org. 1812, Sandia National Laboratories, Albuquerque, NM 87185
Kenneth J. Shea
Affiliation:
Department of Chemistry, University of California Irvine, Irvine, CA 92717
Edward M. Russick
Affiliation:
Org. 1812, Sandia National Laboratories, Albuquerque, NM 87185
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Abstract

We report the preparation of a new class of organic/inorganic hybrid aerogels from aryl-bridged polysilsesquioxanes [1]. l,4-Bis(triethoxysilyl)benzene and 4,4'-bis(triethoxysilyl)-biphenyl were sol-gel processed to form phenyl- and biphenyl-bridged polysilsesquioxane gels (Figure 1, structures 1 and 2, respectively). The gels were then dried using supercritical carbon dioxide extraction. It was discovered that aryl-bridged polysilsesquioxane aerogels are indeed formed, but with a pronounced influence on surface area from the reaction conditions used in preparing the initial gels. Specifically, high surface aerogels ( up to 1750 m2/g) are obtained from gels prepared with either acid or base catalysts. With reduced concentrations of base catalyst, however, supercritical processing afforded phenyl-bridged xerogel-like materials, The materials were characterized by nitrogen sorption surface analysis, and by transmission electron microscopy.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 271: Symposium N – Better Ceramics Through Chemistry V , 1992 , 699
Copyright
Copyright © Materials Research Society 1992

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References

REFERENCES

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