The present invention relates to microfibrous cellulose capable of exhibiting an excellent dispersibility stability and an excellent coating suitability when added to paint.

To this end, the present invention provides fibrous cellulose having a fiber width of 1,000 nm or less and containing an ionic substituent. An amount of the ionic substituent in the fibrous cellulose is 0.10 mmol/g or more and 1.50 mmol/g or less. A polymerization degree of the fibrous cellulose is 150 or more and 515 or less. When the fibrous cellulose is dispersed in a dispersion solvent containing water and isopropanol to obtain a dispersion fluid having a 7:3 mass ratio of water and isopropanol and a viscosity of 2,500 mPa.Math.s at 23° C., and the dispersion fluid is stirred under predetermined stirring conditions, a viscosity change rate falls within ±50% as calculated by the following formula:

viscosity change rate (%)=(viscosity after stirring−viscosity before stirring)/viscosity before stirring×100

In a method for preparing nanofibrillar cellulose, fibrous dispersion of ionically charged cellulose is repeatedly passed through a mechanical process of disrupting fibers into fibrils until the viscosity starts to decrease. The number average diameter of the nanofibrillar cellulose after the mechanical process is in the range of 2-10 nm, and the zero-shear viscosity is below 10 Pa.Math.s, preferably below 1 Pa.Math.s, when measured in the concentration of 0.5 wt-%. The nanofibrillated cellulose is low aspect ratio nanofibrillated cellulose (NFC-L).

In a method for preparing nanofibrillar cellulose, fibrous dispersion of ionically charged cellulose is repeatedly passed through a mechanical process of disrupting fibers into fibrils until the viscosity starts to decrease. The number average diameter of the nanofibrillar cellulose after the mechanical process is in the range of 2-10 nm, and the zero-shear viscosity is below 10 Pa.Math.s, preferably below 1 Pa.Math.s, when measured in the concentration of 0.5 wt-%. The nanofibrillated cellulose is low aspect ratio nanofibrillated cellulose (NFC-L).

This invention discloses methods for producing modified cellulose, modified nanocellulose, modified nanocellulose functionalized with other functional species, and derivatives thereof. The present invention also provides cellulose, nanocellulose, and their derivatives that are safe to use inside an animal or human body and are biocompatible without costly purification. These cellulose or nanocellulose materials can be used in many different applications, including carrier for pharmaceutical active agents and other medical devices.

This invention discloses methods for producing modified cellulose, modified nanocellulose, modified nanocellulose functionalized with other functional species, and derivatives thereof. The present invention also provides cellulose, nanocellulose, and their derivatives that are safe to use inside an animal or human body and are biocompatible without costly purification. These cellulose or nanocellulose materials can be used in many different applications, including carrier for pharmaceutical active agents and other medical devices.

The present invention provides a process for the preparation of essential oil modified nanocellulose and applications thereof. The invention further provides a process wherein the essential oil is covalently bonded with the nanocellulose such that the essential oil does not leach out. The edible coatings comprising the developed essential oil modified nanocellulose thus exhibit a prolonged antimicrobial effect.

Provided is a carboxymethylated microfibrillated cellulose fiber having a Canada standard freeness of less than 200 mL and an average fiber diameter of not less than 500 nm. Said fiber provides a composition having excellent water retention ability.

The invention relates to a method for modifying nanofibrillar cellulose composition, comprising—preparing fibrous dispersion of ionically charged nanofibrillar cellulose (NFC), and—applying heat treatment at a temperature of at least 90° C. to the fibrous dispersion until the viscosity of NFC starts to decrease. The viscosity of the heat-treated NFC is reversible by applying shear forces to the NFC.

The invention relates to a method for modifying nanofibrillar cellulose composition, comprising—preparing fibrous dispersion of ionically charged nanofibrillar cellulose (NFC), and—applying heat treatment at a temperature of at least 90° C. to the fibrous dispersion until the viscosity of NFC starts to decrease. The viscosity of the heat-treated NFC is reversible by applying shear forces to the NFC.

The present disclosure provides a method for preparing an aerogel or a foam, the method comprising: forming a reaction mixture comprising a cellulose nanofibril gel, a first solvent, and one or more crosslinking agents under conditions sufficient to crosslink the gel; and contacting the crosslinked gel with a second solvent under conditions sufficient to dry the crosslinked gel, thereby forming an aerogel or foam.