Provided are a hydroxyalkylalkyl cellulose excellent in formability and not causing marked delay in disintegration when added even in a small amount; a solid preparation including the hydroxyalkylalkyl cellulose; and a method for producing the solid preparation. More specifically, provided are a hydroxyalkylalkyl cellulose for tableting having a specific surface area of from 0.5 to 5.0 m.sup.2/g as measured by BET and a solid preparation including the hydroxyalkylalkyl cellulose. Also provided is a method for producing the hydroxyalkylalkyl cellulose for tableting, including the steps of: bringing pulp into contact with an alkali metal hydroxide solution to obtain an alkali cellulose, reacting the alkali cellulose with an etherifying agent to obtain a first hydroxyalkylalkyl cellulose, grinding the first hydroxyalkylalkyl cellulose, and subjecting the ground first hydroxyalkylalkyl cellulose to hydrolysis in the presence of an acid catalyst or oxidative degradation in the presence of an oxidant to obtain a second hydroxyalkylalkyl cellulose.

Provided are a hydroxyalkylalkyl cellulose excellent in formability and not causing marked delay in disintegration when added even in a small amount; a solid preparation including the hydroxyalkylalkyl cellulose; and a method for producing the solid preparation. More specifically, provided are a hydroxyalkylalkyl cellulose for tableting having a specific surface area of from 0.5 to 5.0 m.sup.2/g as measured by BET and a solid preparation including the hydroxyalkylalkyl cellulose. Also provided is a method for producing the hydroxyalkylalkyl cellulose for tableting, including the steps of: bringing pulp into contact with an alkali metal hydroxide solution to obtain an alkali cellulose, reacting the alkali cellulose with an etherifying agent to obtain a first hydroxyalkylalkyl cellulose, grinding the first hydroxyalkylalkyl cellulose, and subjecting the ground first hydroxyalkylalkyl cellulose to hydrolysis in the presence of an acid catalyst or oxidative degradation in the presence of an oxidant to obtain a second hydroxyalkylalkyl cellulose.

The invention provides a nanomaterial of polyglycerol grafted cellulose nanocrystal dendrimer and a preparation method thereof. In the present invention, the cotton linter pulp is pulverized into flocculent fibers, fed to sulfuric acid, and reacted. After centrifugation, dialysis and ultrasonic cell disruption, cellulose nanocrystals are obtained. Carboxylated cellulose nanocrystals are further obtained after oxidation with TEMPO, dialysis, and freeze-drying. The carboxylated nanocrystals are further added to DMF, and under a nitrogen atmosphere, glycidol is grafted to the hydroxyl groups on the surface by heating with stirring. After the reaction is completed, the product is centrifuged, dried under vacuum, dialyzed, and freeze dried to obtain a nanomaterial of primary polyglycerol grafted cellulose nanocrystals. Dendrimers with different particle size ranges can be prepared by controlling the number of reactions, which contain a large number of hydroxyl groups on the surface, and are amenable to various modifications.

The invention provides a nanomaterial of polyglycerol grafted cellulose nanocrystal dendrimer and a preparation method thereof. In the present invention, the cotton linter pulp is pulverized into flocculent fibers, fed to sulfuric acid, and reacted. After centrifugation, dialysis and ultrasonic cell disruption, cellulose nanocrystals are obtained. Carboxylated cellulose nanocrystals are further obtained after oxidation with TEMPO, dialysis, and freeze-drying. The carboxylated nanocrystals are further added to DMF, and under a nitrogen atmosphere, glycidol is grafted to the hydroxyl groups on the surface by heating with stirring. After the reaction is completed, the product is centrifuged, dried under vacuum, dialyzed, and freeze dried to obtain a nanomaterial of primary polyglycerol grafted cellulose nanocrystals. Dendrimers with different particle size ranges can be prepared by controlling the number of reactions, which contain a large number of hydroxyl groups on the surface, and are amenable to various modifications.

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.

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.

The present description is related to methods for derivatizing cellulose pulp, and to products obtainable using said method.

Carboxymethylated cellulose nanofibers in which the cellulose type I crystallinity is 60% or higher, the aspect ratio is 350 or lower, and the transmittance of light having a wavelength of 660 nm when the carboxymethylated cellulose nanofibers are made into an aqueous dispersion having a solids fraction of 1% (w/v) is 60% or higher.

The present disclosure relates to the environmentally preparation of nanocellulose and derivatives thereof. The invention further relates to the preparation of cellulose derivatives.

The present disclosure relates to the environmentally preparation of nanocellulose and derivatives thereof. The invention further relates to the preparation of cellulose derivatives.