Process for making crosslinked polyvinylpyrrolidone with low swell volume
US6512066B1 · kind B1 · utility
7Cited by
2References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2002 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Feb 14, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F126/10
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A two-step, base-catalyzed process for making crosslinked polyvinylpyrrolidone (PVP-P) having a low swell volume is disclosed. A crosslinker is generated “in situ” in the first step by heating a basic aqueous mixture containing a relatively low concentration of N-vinylpyrrolidone under added inert gas pressure. In a second step, the reactor temperature is reduced to initiate polymerization. The process is a productive way to make PVP-P that is easy to isolate and purify. The polymer has a swell volume less than about 40 mL H2O/10 g polymer, which makes it valuable for beverage clarification.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.