Abstract: A cellulose nanofiber (CNF) powder of the present invention contains cellulose nanofibers, and a hydrophobic polymer that is chemically bonded to at least some of the —OH groups of the cellulose nanofibers. The CNF powder has the ability to be dispersed in water and to return to a powder form again when an aqueous dispersion of the CNF powder is dried. The distance between the fibers in the CNF powder in a dry state is 3 nm or more, and preferably 8 to 12 nm. Since the distance between the fibers in the conventional cellulose nanofibers is about 1 nm, the present invention reduces the Van der Waals force between the fibers (i.e., the force of attraction between the fibers) to one millionth of that of the conventional cellulose nanofibers. Thus, the present invention provides the CNF powder that can be used in a powder form, and that can also be reversibly changed between a powder state and a dispersed state in water, and a method for producing the CNF powder.

Abstract: A cellulose nanofiber (CNF) powder of the present invention contains cellulose nanofibers, and a hydrophobic polymer that is chemically bonded to at least some of the —OH groups of the cellulose nanofibers. The CNF powder has the ability to be dispersed in water and to return to a powder form again when an aqueous dispersion of the CNF powder is dried. The distance between the fibers in the CNF powder in a dry state is 3 nm or more, and preferably 8 to 12 nm. Since the distance between the fibers in the conventional cellulose nanofibers is about 1 nm, the present invention reduces the Van der Waals force between the fibers (i.e., the force of attraction between the fibers) to one millionth of that of the conventional cellulose nanofibers. Thus, the present invention provides the CNF powder that can be used in a powder form, and that can also be reversibly changed between a powder state and a dispersed state in water, and a method for producing the CNF powder.