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A Rapid Supercritical Extraction Process for the Production of Silica Aerogels*

Published online by Cambridge University Press:  10 February 2011

J. F. Poco ,
P. R. Coronado ,
R. W. Pekala  and
L. W. Hrubesh
J. F. Poco
Affiliation:
Chemistry & Materials Science Department, Lawrence Livermore National Laboratory, Livermore, CA94550 hrubeshl@llnl.gov
P. R. Coronado
Affiliation:
Chemistry & Materials Science Department, Lawrence Livermore National Laboratory, Livermore, CA94550 hrubeshl@llnl.gov
R. W. Pekala
Affiliation:
Chemistry & Materials Science Department, Lawrence Livermore National Laboratory, Livermore, CA94550 hrubeshl@llnl.gov
L. W. Hrubesh
Affiliation:
Chemistry & Materials Science Department, Lawrence Livermore National Laboratory, Livermore, CA94550 hrubeshl@llnl.gov
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Abstract

Silica aerogels are a special class of porous materials in which both the pore size and interconnected particle size have nanometer dimensions. This structure imparts unique optical, thermal, acoustic, and electrical properties to these materials. Transmission electron microscopy and small angle x-ray scattering show that this nanostructure is sensitive to variations in processing conditions that influence crosslinking chemistry and growth processes prior to gelation. Recently, Lawrence Livermore National Laboratory (LLNL) has demonstrated that a Rapid Supercritical Extraction (RSCE) process can be used to prepare near-net shape silica aerogels in hours rather than days. Preliminary data from RSCE silica aerogels show that they have improved mechanical properties and slightly lower surface areas than their conventionally dried counterparts, while not compromising their optical and thermal performance.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 431: Symposium P – Microporous and Macroporous Materials , 1996 , 297
Copyright
Copyright © Materials Research Society 1996

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Footnotes

*

Work performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48

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