Production method for modified vinyl alcohol-based polymer particles and particles obtained using same
US12227607B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 2020 |
| Grant date | Feb 18, 2025 |
| Priority date | — |
| Expiry date | Jan 29, 2042 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F2810/30
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method of producing modified vinyl alcohol-based polymer particles, includes mixing vinyl alcohol-based polymer particles with a mixed medium containing unsaturated carboxylic acid, an acid catalyst, and water, wherein, by mixing the vinyl alcohol-based polymer particles with the mixed medium, the vinyl alcohol-based polymer particles are reacted with the unsaturated carboxylic acid to obtain modified vinyl alcohol-based polymer particles containing a vinyl ester unit represented by a formula (2) below, having a vinyl alcohol unit content based on the total constitutional units from 95 to 99.99 mol %, and having an average particle diameter from 50 to 2000 μm. The production method does not cause the problem of the residual sulfur content derived from a liquid medium used for reaction and is also capable of modifying the vinyl alcohol-based polymer particles while maintaining the particle shape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.