Silica xerogel sintering

Fig. 24. Nitrogen adsorption-desorption isotherms for silica xerogel sintered in vacuo.

In order to convert xerogels to dense, stable, solid materials, a further thermal treatment is required. In this stabilization step the gel is dehydrated, dehydroxylated and sintered. Thus all surface hydroxyls are removed and the material is fully densified. Since this work discusses the characterization and modification of porous silica xerogel we will not further discuss the processes in this step. The reader is... 

Reconstruction, of surface, 580 Redispersion, 248, 250. See also Peptization, Stability of sols Redistribution. See Reconstruction, of surface. Restructuring Reduced time, 678, 685, 688-689, 696 Reduction, 289 Reedmergnerite, 780 Reesterification. See Esterification Refractive index, 275, 465, 594 film, 790, 852 graded, 844-847 of partially sintered gels, 768 of silica, 766-767 of strontium silicate, 777, 779 silica xerogels, 581, 583... 

Kortesuo P, Ahola M, Karlsson S, Kangasniemi I, Kiesvaara J, Yli-Urpo A. 1999. Sol-gel-processed sintered silica xerogel as a carrier in controlled drug delivery./Btomed Mater Res 44 162-167. 

Four silica samples, Aerogel S, Santocel C, a Davison xerogel, and Linde silica have been subjected to vacuum sintering treatments. 

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