Cellulose nanofiber production method of same and cellulose nanofiber dispersion
AssigneeThe University of Tokyo
InventorsAkira Isogai, Tsuguyuki Saito
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Abstract
The cellulose nanofiber production method of the present invention comprises an oxidation treatment step for oxidizing native cellulose in a neutral or acidic reaction solution containing an N-oxyl compound and an oxidizing agent that oxidizes aldehyde groups, and a dispersion step for dispersing the native cellulose in a medium following the oxidation treatment step. According to the production method of the present invention, a cellulose nanofiber is provided that has long fibers and demonstrates high strength.
Claims21
1-15. (canceled)
A cellulose nanofiber production method, comprising:
- oxidizing native cellulose in a neutral or acidic reaction solution, said reaction solution comprising an N-oxyl compound and an oxidizing agent that oxidizes aldehyde groups, and
- dispersing the native cellulose in a medium following oxidizing the native cellulose.
The cellulose nanofiber production method of claim 1, wherein oxidizing native cellulose includes adding a buffer to the reaction solution.
The cellulose nanofiber production method of claim 1, wherein the oxidizing agent comprises a halous acid or salt thereof.
The cellulose nanofiber production method of claim 1, wherein the oxidizing agent comprises a mixture of hydrogen peroxide and an oxidizing enzyme.
The cellulose nanofiber production method of claim 1, wherein the oxidizing agent comprises a peracid.
The cellulose nanofiber production method of claim 1, wherein the pH of the reaction solution is from 4 to 7.
The cellulose nanofiber production method of claim 1, wherein oxidizing native cellulose includes adding a hypohalous acid or salt thereof to the reaction solution.
The cellulose nanofiber production method of claim 1, wherein the N-oxyl compound is 2,2,6,6-tetramethyl-1-piperidine-N-oxyl.
The cellulose nanofiber production method of claim 1, wherein dispersing the native cellulose comprises mechanical defibration treatment.
A cellulose nanofiber having a maximum fiber diameter of 1000 nm or less and a number average fiber diameter of 2 to 150 nm, and having a surface,
- wherein at least a portion of the surface comprises glucuronic acid.
A cellulose nanofiber having a maximum fiber diameter of 1000 nm or less and a number average fiber diameter of 2 to 150 nm,
- wherein the content of aldehyde groups in the cellulose nanofiber composition is less than 0.05 mmol/g based on the weight of the cellulose.
Dependencies are inferred from the claim text.