Flexible, low-density polymer crosslinked silica aerogels

Polymer ◽  
2006 ◽  
Vol 47 (16) ◽  
pp. 5754-5761 ◽  
Author(s):  
Lynn A. Capadona ◽  
Mary Ann B. Meador ◽  
Antonella Alunni ◽  
Eve F. Fabrizio ◽  
Plousia Vassilaras ◽  
...  
Keyword(s):  
Silica Aerogels ◽  
Low Density

NMR studies of superfluid in low density silica aerogels

2003 ◽  
Vol 329-333 ◽  
pp. 292-295
Author(s):  
J.E. Baumgardner ◽  
L.V. Polukhina ◽  
Y. Lee ◽  
J.F. Poco ◽  
L.W. Hrubesh ◽  
...  
Keyword(s):  
Silica Aerogels ◽  
Low Density ◽  
Nmr Studies

Strong, Low-Density Nanocomposites by Chemical Vapor Deposition and Polymerization of Cyanoacrylates on Aminated Silica Aerogels

2009 ◽  
Vol 1 (7) ◽  
pp. 1364-1369 ◽  
Author(s):  
Dylan J. Boday ◽  
Robert J. Stover ◽  
Beatrice Muriithi ◽  
Michael W. Keller ◽  
Jason T. Wertz ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Silica Aerogels ◽  
Low Density

Super Thermal Insulating SiO2 Cryogels Prepared by Vacuum Freeze Drying

2010 ◽  
Vol 105-106 ◽  
pp. 851-854 ◽  
Author(s):  
Li Fen Su ◽  
Lei Miao ◽  
Gang Xu ◽  
Sakae Tanemura
Keyword(s):  
Freeze Drying ◽  
Ambient Pressure ◽  
Supercritical Drying ◽  
Silica Aerogels ◽  
Base Catalysis ◽  
Low Density ◽  
Solvent Exchange ◽  
Acid Base ◽  
Thermal Insulating ◽  
Silica Precursor

Traditionally, silica aerogels with low thermal conductivity are prepared by supercritical drying, however, the process is expensive and hazardous due to it run in autoclaves. In order to overcome these disadvantages, a cheaper and safer process, drying at ambient pressure has been developed for decades, but tedious repetitive gel washing and solvent exchange steps are involved. Therefore, in the present study, a novel vacuum freeze-drying was utilized to prepare the super thermal insulating SiO2 cryogels. The wet gels were synthesized via acid-base catalysis using tetraethoxysilane (TEOS) as a silica precursor and ethanol as a solvent. After vacuum freeze drying, nanoporous SiO2 cryogels with low density in the range of 0.08-0.15 g/cm3 were obtained.

Hydrophobic and low density silica aerogels dried at ambient pressure using TEOS precursor

2009 ◽  
Vol 471 (1-2) ◽  
pp. 296-302 ◽  
Author(s):  
Jyoti L. Gurav ◽  
A. Venkateswara Rao ◽  
Uzma K.H. Bangi
Keyword(s):  
Ambient Pressure ◽  
Silica Aerogels ◽  
Low Density

Thermal. Acoustical and Structural Properties of Silica Aerogels

1986 ◽  
Vol 73 ◽  
Author(s):  
J. Fricke ◽  
G. Reichenauer
Keyword(s):  
Optical Properties ◽  
Structural Properties ◽  
Silica Aerogels ◽  
Low Density ◽  
Density Structure ◽  
Secondary Particles ◽  
Window Systems ◽  
Fractal Properties ◽  
Primary Particles ◽  
Highly Porous

ABSTRACTSilica aerogels either in monolithic or in granular form provide excellent thermal insulation and thus may be used as superinsulating spacer in all kinds of window systems. Highly porous aerogels also are exciting acoustic materials with sound velocities in the order of 100 m/s and acoustic impedances between 104 and 105 kg/(m2·s). Silica aerogels produced from TMOS seem to consist of massive primary particles (ø ≅ 1 nm, ρ ≅ 2000 kg/m3) which form secondary particles (ø ≅ 5 to 6 nm, ρ ≅800 kg/in 3) displaying fractal properties (D≅ 2). The further buildup creates the highly porous low-density structure which is responsible for the special thermal, acoustical and optical properties of aerogels. Above about 100 nm, transparent aerogels should be homogeneous.

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