Method for producing metal oxide aerogels
US5409683A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 1994 |
| Grant date | Apr 25, 1995 |
| Priority date | — |
| Expiry date | Jul 7, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C1/006
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A two-step hydrolysis-condensation method was developed to form metal oxide aerogels of any density, including densities of less than 0.003g/cm.sup.3 and greater than 0.27g/cm.sup.3. High purity metal alkoxide is reacted with water, alcohol solvent, and an additive to form a partially condensed metal intermediate. All solvent and reaction-generated alcohol is removed, and the intermediate is diluted with a nonalcoholic solvent. The intermediate can be stored for future use to make aerogels of any density. The aerogels are formed by reacting the intermediate with water, nonalcoholic solvent, and a catalyst, and extracting the nonalcoholic solvent directly. The resulting monolithic aerogels are hydrophobic and stable under atmospheric conditions, and exhibit good optical transparency, high clarity, and homogeneity. The aerogels have high thermal insulation capacity, high porosity, mechanical strength and stability, and require shorter gelation times than aerogels formed by conventional methods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.