Magnetic polymer latex and preparation process
US4358388A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1981 |
| Grant date | Nov 9, 1982 |
| Priority date | — |
| Expiry date | Apr 16, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2446/64
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Magnetic-polymer latex having a concentration of less than 65% by weight of hydrophobic vinyl aromatic polymer particles. The polymer particles have diameters from 0.03 to 5 microns and also have dispersed therein a magnetically-charged material in an amount of from 0.5 to 50% by weight with respect to the polymer portion of the polymer particles. A process for preparing magnetic-polymer latices. Magnetically charged particles are dispersed in an organic phase comprising an organically soluble initiator and an organic monomeric component selected from the group consisting of a single vinyl aromatic monomer and a combination of a single vinyl aromatic monomer and a copolymerizing monomer. The dispersion so obtained is mixed with an aqueous solution containing an emulsifying agent and the mixture is homogenized. Polymerization is then effected to form a magnetic-polymer latex containing hydrophobic vinyl aromatic polymer particle. More organic monomer component may be added immediately prior to or during polymerization. Alternatively, the magnetically-charged material may be dispersed into an organic phase comprising an organically soluble initiator and a water-soluble organic compou…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.