Method of forming polymer microspheres
US5599889A · kind A · utility
Inventors
Key dates
| Filing date | Aug 16, 1994 |
| Grant date | Feb 4, 1997 |
| Priority date | — |
| Expiry date | Aug 16, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F212/18
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Disclosed herein is a method of forming cross-linked polymer microspheres, comprising the steps of: PA1 forming a reaction mixture essentially free of stabilizer and comprising a polymerization medium, a di-vinyl cross-linking agent, a functional co-monomer which is copolymerizable with said cross-linking agent and a radical initiator, with said cross-linking agent, said functional co-monomer and said initiator being soluble in said polymerization medium; PA1 subjecting said reaction mixture to conditions selected to form microspheres with two modes of stabilization, a first being provided by cross-linking, and a second being provided by short stabilizing chains extending outwardly from the microsphere and into said medium, said stabilizing chains having a sufficient concentration of said functional co-monomer to have steric stability in said medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.