Purification of cellulose ether reaction product
US4229572A · kind A · utility
9Cited by
9References
17Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1979 |
| Grant date | Oct 21, 1980 |
| Priority date | — |
| Expiry date | Mar 5, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08B11/20
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
In the preparation of organosoluble cellulose ethers, the content of alkali metal (hydroxides and the salts thereof) in the resulting cellulose ether is reduced by forming a solution of the cellulose ether and an organic solvent, converting the alkali metal hydroxide therein to an alkali metal salt and heating the resulting solution at conditions sufficient to (1) increase the size of the alkali metal salt particles and (2) remove any water therefrom. Filtering the resulting mixture and drying the filtrate yields a cellulose ether containing a very small percentage of alkali metal salt, e.g., often less than about 500 ppm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.