Pyrolysis of ceramic precursors to nanoporous ceramics
US5872070A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 1997 |
| Grant date | Feb 16, 1999 |
| Priority date | — |
| Expiry date | Jan 3, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/831
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention provides for amorphous, nanoporous, ceramic material having a surface area in excess of 70 m.sup.2 /gm and characterized by a high content of open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.03 cm.sup.3 /gm of the ceramic. The invention also provides a process for the preparation of such nanoporous ceramics wherein a ceramic precursor polymer or oligomer is gradually heated in the presence of an inert gas or vacuum up to a maximum temperature in the range of greater than 400.degree. C. up to about 650.degree. C. Optionally, the process may also include a crosslinking step conducted prior to the heating step wherein the precursor polymer or oligomer is heated in the presence of a crosslinking agent capable of undergoing addition or substitution reactions with backbone atoms present in said precursor material, at an intermediate temperature of about 100.degree. to 400.degree. C. for a period of time sufficient to crosslink said precursor material, followed by pyrolysis of the crosslinked material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.