Embodiments of the invention provide regioselectively substituted carbohydrate and polysaccharide derivatives, such as cellulose esters, and methods for preparing them. Particular methods of the invention include deacylation of esters using tetrabutylammonium fluoride to obtain selective substitution at desired hydroxyl position(s) of the ester. Preferred is deacylation of an ester, which shows selectivity for removal of acyl groups from the ester of the secondary alcohols at C-2 and C-3, and which affords cellulose-6-O-esters with high regioselectivity by a simple one-step process employing no protective groups. Inventive regioselectively substituted cellulose esters can be prepared by such methods to obtain esters with the following anhydroglucose repeating units: ##STR00001## wherein R.sup.1, R.sup.2, and R.sup.3 are each independently chosen from a hydrogen atom, and, whether substituted or unsubstituted, branched or unbranched, an alkanoyl group, an aroyl group, and a heteroaroyl group. In embodiments, the alkanoyl, aroyl and heteroaroyl groups can comprise from 1-20 carbon atoms.

Embodiments of the invention provide regioselectively substituted carbohydrate and polysaccharide derivatives, such as cellulose esters, and methods for preparing them. Particular methods of the invention include deacylation of esters using tetrabutylammonium fluoride to obtain selective substitution at desired hydroxyl position(s) of the ester. Preferred is deacylation of an ester, which shows selectivity for removal of acyl groups from the ester of the secondary alcohols at C-2 and C-3, and which affords cellulose-6-O-esters with high regioselectivity by a simple one-step process employing no protective groups. Inventive regioselectively substituted cellulose esters can be prepared by such methods to obtain esters with the following anhydroglucose repeating units: ##STR00001## wherein R.sup.1, R.sup.2, and R.sup.3 are each independently chosen from a hydrogen atom, and, whether substituted or unsubstituted, branched or unbranched, an alkanoyl group, an aroyl group, and a heteroaroyl group. In embodiments, the alkanoyl, aroyl and heteroaroyl groups can comprise from 1-20 carbon atoms.

Degradable materials are provided that may be utilized in various wellbore treatment fluids, such as hydraulic fracturing fluids. In particular, the degradable materials can be formed from cellulose esters that are capable of effectively degrading at specific rates when exposed to the aqueous environments commonly found in wellbores. More particularly, the degradable materials can be in the form of degradable fibers that are formed from the cellulose esters described herein.

The present invention is to provide a cellulose acetate that has a low total degree of acetyl substitution and a degree of acetyl substitution at 6-position that is lower compared to the degrees of acetyl substitution at 2-position and 3-position of a glucose ring, and has excellent water solubility. A cellulose acetate having: a total degree of acetyl substitution of 0.4 or greater and 0.9 or less, a proportion of a degree of acetyl substitution at 6-position in the total degree of acetyl substitution of 0% or greater and 18% or less, and a light transmittance at 660 nm of 5% or greater in 4 wt. % aqueous solution.

The present invention is to provide a cellulose acetate that has a low total degree of acetyl substitution and a degree of acetyl substitution at 6-position that is lower compared to the degrees of acetyl substitution at 2-position and 3-position of a glucose ring, and has excellent water solubility. A cellulose acetate having: a total degree of acetyl substitution of 0.4 or greater and 0.9 or less, a proportion of a degree of acetyl substitution at 6-position in the total degree of acetyl substitution of 0% or greater and 18% or less, and a light transmittance at 660 nm of 5% or greater in 4 wt. % aqueous solution.

A fibrous cellulose has an average fiber width of 0.1 m or more and has a part or all of hydroxyl groups replaced with carbamate groups, in which a replacement ratio with the carbamate group is 1.0 mmol/g or more, and a fine ratio is 30% or more. A fibrous cellulose composite resin contains a fibrous cellulose and a resin, and the above fibrous cellulose In manufacturing fibrous cellulose, a cellulose raw material and urea or the like are subjected to a heat treatment to replace a part or all of hydroxyl groups of the cellulose raw material with carbamate groups, defibration is performed within a range in which an average fiber width is 0.1 m or more, the heat treatment is performed such that a replacement ratio with the carbamate group is 1.0 mmol/g or more, and the defibration is performed until a fine ratio reaches 30% or more.

A fibrous cellulose has an average fiber width of 0.1 m or more and has a part or all of hydroxyl groups replaced with carbamate groups, in which a replacement ratio with the carbamate group is 1.0 mmol/g or more, and a fine ratio is 30% or more. A fibrous cellulose composite resin contains a fibrous cellulose and a resin, and the above fibrous cellulose In manufacturing fibrous cellulose, a cellulose raw material and urea or the like are subjected to a heat treatment to replace a part or all of hydroxyl groups of the cellulose raw material with carbamate groups, defibration is performed within a range in which an average fiber width is 0.1 m or more, the heat treatment is performed such that a replacement ratio with the carbamate group is 1.0 mmol/g or more, and the defibration is performed until a fine ratio reaches 30% or more.

This invention relates generally to a method of treating a crop with an agricultural product, where the method includes the steps of incorporating a cellulose nanocrystal-based emulsion into an agrochemical to produce the agricultural product and applying said agricultural product to said crop. The cellulose nanocrystal-based emulsion includes a continuous aqueous phase and a dispersed oil phase, where the continuous aqueous phase includes between about 0.25% and about 3% (w/w) of sulfonated cellulose nanocrystals, between about 0.25% and about 1% (w/w) of co-stabilizing biopolymer, and up to about 3.0% (w/w) of cationic crosslinker. The dispersed oil phase includes a plant-based oil.

This invention relates generally to a method of treating a crop with an agricultural product, where the method includes the steps of incorporating a cellulose nanocrystal-based emulsion into an agrochemical to produce the agricultural product and applying said agricultural product to said crop. The cellulose nanocrystal-based emulsion includes a continuous aqueous phase and a dispersed oil phase, where the continuous aqueous phase includes between about 0.25% and about 3% (w/w) of sulfonated cellulose nanocrystals, between about 0.25% and about 1% (w/w) of co-stabilizing biopolymer, and up to about 3.0% (w/w) of cationic crosslinker. The dispersed oil phase includes a plant-based oil.