ISSN:
0001-1541
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Microporous silica gels can be made by polymerizing partially hydrolyzed tetramethoxysilane sols present in the aqueous phase of bicontinuous microemulsions stabilized with didodecyldimethylammonium bromide. When vacuum-dried, the gels made in microemulsions have about twice the specific surface area of conventional vacuum-dried silica gels. They have 70% of the specific area of supercritically dried gels. Small-angle X-ray Scattering measurements in these gels show two characteristic sizes. One size, around 24Å, in the original microemulsion is retained during polymerization, but lost when the detergent is extracted. The second size grows with the square root of time during the polymerization, suggesting diffusion-controlled gelation.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/aic.690410115
Permalink