Cellulose derivatives
AssigneeBetulium Oy
InventorNikolaos Pahimanolis
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Abstract
The present invention provides a method for derivatizing cellulose pulp at high solids content or even at a fully dry state without pretreating the cellulose, the method comprising preparing a reaction medium comprising urea and at least one derivatization reagent; carrying out a chemical derivatization reaction between the at least one derivatization reagent and the cellulose pulp in a reaction system comprising the cellulose pulp in contact with the reaction medium; and optionally purifying and/or recovering the derivatized cellulose product. The present description also relates to products obtainable using said method.
Claims19
A method for derivatizing cellulose pulp selected from hardwood pulp, softwood pulp, and dissolving pulp, the method comprising:
- a. preparing a reaction medium comprising urea and at least one derivatization reagent;
- b. carrying out a heterogenous chemical derivatisation reaction between the at least one derivatization reagent and the cellulose pulp in a reaction system comprising the cellulose pulp in contact with the reaction medium, and having a water content of 0-20% by weight, to provide a derivatized cellulose product;
- and
- c. fibrillating to obtain derivatized cellulose nanofibers or derivatized microfibrillated cellulose;
- wherein the derivatization reagent is a cationization reagent and the reaction medium comprises water 10-20% by weight.
Dependencies are inferred from the claim text.