Functionalized magnetizable microspheres and preparation thereof
US7553542B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 2007 |
| Grant date | Jun 30, 2009 |
| Priority date | — |
| Expiry date | Aug 13, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2998
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention discloses a two-stage process for preparing functionalized magnetizable microspheres. The first stage includes forming an inner shell of styrene polymer or styrene copolymer around magnetizable nano particles having a monolayer of a non-water-soluble dispersing agent coated thereon. The second stage includes forming an outer shell of styrene polymer or styrene copolymer with sulfate (SO4−) bounded thereto around the inner shell by free radical polymerization. Preferably, nano particles of a noble metal are deposited on the surface of the outer shell. The magnetizable microspheres prepared by the process of the present invention have a size of 100-1000 nm, and the thickness ratio of the inner shell to the outer shell ranges from 10:1 to 1:10.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.