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Engineering of Porosity in Amorphous Materials. Plasma Oxidation of Hydrocarbon Templates in Polysilsesquioxanes*

Published online by Cambridge University Press:  21 February 2011

Douglas A. Loy
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185
Richard J. Buss
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185
Roger A. Assink
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185
Kenneth J. Shea
Affiliation:
Department of Chemistry, University of California, Irvine, CA 92717.
Henry Oviatt
Affiliation:
Department of Chemistry, University of California, Irvine, CA 92717.
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Abstract

Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis(triethoxysilyl)-arylene monomers 1-4, and alkylene monomers 5-9. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m2/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state 29Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The alkylene-bridged polysilsesquioxanes were non-porous. Oxygen plasma treatment afforded silica gels with mesoporosity. The porosity in the silica gels appears to arise entirely from the oxidation of the alkylene spacers.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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References

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