Homogeneous synthesis of cellulose ethers in ionic liquids
AssigneeSE Tylose GmbH & Co. KG
InventorsEugen Moellmann, Thomas Heinze, Tim Liebert, Sarah Koehler
Life of this patent
Estimating the term…
Abstract
The invention is directed to a simple and new method for the homogeneous synthesis of cellulose ethers. Ionic liquids are not only used as solvent, but also as reaction media for the homogeneous etherification of cellulose. The dissolved cellulose is treated with the etherification agent in the absence of organic and/or inorganic bases and in the absence and/or in the presence of moderate amounts of water. The obtained cellulose ethers show new distributions of substitution on the polymer chain, resulting in new properties and applications.
Claims24
A process for the production of cellulose ethers comprising the steps of
- dissolving cellulose in a solvent comprising an ionic liquid in the absence of (a) inorganic bases;
- and (b) organic bases that are not ionic liquids,
- adding to the dissolved cellulose at least one etherifying agent without addition of organic or inorganic base to the solution in order to produce a cellulose ether,
- adding the reaction mixture to a non-solvent for the cellulose ether obtained in the etherifying reaction, and thereby precipitating the cellulose ether,
- separating off the cellulose ether and
- purifying the cellulose ether.
Dependencies are inferred from the claim text.