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Precursor Chemistry and the Structure of Silica Aerogels*

Published online by Cambridge University Press:  25 February 2011

D. W. Schaefer ,
C. J. Brinker ,
J. P. Wilcoxon ,
D.-Q. Wu ,
J. C. Phillips  and
B. Chu
D. W. Schaefer
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–5800
C. J. Brinker
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–5800
J. P. Wilcoxon
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–5800
D.-Q. Wu
Affiliation:
Chemistry Department, State University of New York, Stony Brook, NY 11794–3400
J. C. Phillips
Affiliation:
Chemistry Dept., State University of New York, Chemistry Dept., Buffalo, NY 11794–3400, and SUNY X3 Beamline, National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, Upton, NY 11973
B. Chu
Affiliation:
Chemistry Department, State University of New York, Stony Brook, NY 11794–3400
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Abstract

Small-angle X-ray scattering is used to characterize the structure of aerogels prepared by two-stage polymerization processes. Second-stage catalysis controls the resistance to collapse during drying with the base-catalyzed system being most resistant. Base catalysis in the second stage leads to compaction of the polymer network on short length scales. This short-scale rigidity makes the networks sufficiently robust to withstand the surface tension forces present during solvent extraction and re-exposure to the atmosphere. Aging in solution also improves aerogel quality. In this case, a dissolution-repolymerization process leads to short length scale circuits and improved rigidity.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 121: Symposium H – Better Ceramics Through Chemistry III , 1988 , 691
Copyright
Copyright © Materials Research Society 1988

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Footnotes

**

B. Chu gratefully acknowledge support of this work by the U.S. Department of Energy under Contract No. DE-FG-02-87ER45237AO01 and the SUNY Beamline under Contract No. DE-FG-02-86ER45231A001 and National Synchrotron Light Source under Contract No. DE-ACO2-76CH00016.

***

J. C. Phillips gratefully acknowledge support of this work by the U.S. Department of Energy under Contract No. DE-FG-02-87ER45237AO01 and the SUNY Beamline under Contract No. DE-FG-02-86ER45231A001 and National Synchrotron Light Source under Contract No. DE-ACO2-76CH00016.

*

This work performed at Sandia National Laboratories, Albuquerque, NM and supported by the U.S. Department of Energy under Contract No. DE-AC-04-76DP00789 for the Office of Basic Energy Sciences, Division of Materials Science.

References

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