Preparation of solvent and polymer redispersible formulations of dried cellulose nanocrystals (CNC)
AssigneeCelluforce Inc.
InventorsPhilippe Bourassa, Myriam Methot, Richard Berry
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Abstract
The disclosure provides redispersible CNC. The CNC disclosed herein is redispersible in non-polar and polar organic solvents as well as polar and non-polar polymers such as polyethylene or polypropylene. The disclosure surprisingly also provides redispersible CNC bearing improved redispersion in aqueous systems and most particularly in high ionic strength aqueous systems which usually require significant mixing energy to achieve dispersion.
Claims15
A redispersible cellulose nanocrystal (CNC) wherein said redispersible CNC is comprising non-covalent ionic adduct of a cationic groups formed from a protonated amine compound and anionic groups formed from titrable acidic groups, wherein said titrable acidic groups are located at the surface of said redispersible CNC, wherein said titrable acidic group is comprising sulfate half-esters, and wherein said redispersible CNC is in an isolated dried form, wherein said amine compound is a monoamine-terminated polyalkane, a monoamine-terminated polyalkylether or a monoamine-terminated polyalkylene imine.
A method for producing an isolated dried redispersible cellulose nanocrystal (CNC) comprising
- i) providing an aqueous suspension of an acidic CNC comprising sulfuric acid;
- ii) mixing an amount of an amine compound with said suspension of an acidic CNC, wherein said amount is sufficient to cause the pH of said suspension to increase to about below the pKa of the protonated amine compound;
- and
- iii) drying the suspension resulting from step ii to produce said redispersible CNC having a titrable acidic group comprising sulfate half-esters.
Dependencies are inferred from the claim text.