Method for preparing anisotropic silica aggregates
US7884153B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 7, 2004 |
| Grant date | Feb 8, 2011 |
| Priority date | — |
| Expiry date | Feb 8, 2027 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/12
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention concerns a method for preparing anisotropic silica aggregates comprising the following steps: a) contacting at least one polymer with non-aggregated silica particles and/or highly dispersed in an aqueous medium, with a ratio R, polymer weight to silica particle surface, ranging between 0.03 and 2 mg/m; 2; and whereof the electrostatic value of the silica particle surface is not less than the value of the charge of the silica particle surface measured in an aqueous phase without added salts at a pH not less than 7; b) consolidating the aggregates obtained at step a) either by heat treatment, or by precipitation of a mineral compound. The invention also concerns a silica aggregate comprising a chaining of elementary particles whereof the number of particles ranges between 5 and 15, whereof 80% of elementary particles are in contact with not more than 2 particles and whereof the greatest distance measurable between 2 points of the aggregate is not more than 5 times the average size of one elementary particle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.