The invention relates to cellulose esters, the ester groups of which are at least partially containing phosphorus and are based on unsaturated carboxylic acids and reactive phosphorus components, wherein the latter are preferably phosphorus derivatives of sugar alcohols or of tartaric acid derivatives. The invention also relates to methods for preparing novel phosphorus-containing cellulose esters and to their use as flame retardants for plastics.

The invention relates to cellulose esters, the ester groups of which are at least partially containing phosphorus and are based on unsaturated carboxylic acids and reactive phosphorus components, wherein the latter are preferably phosphorus derivatives of sugar alcohols or of tartaric acid derivatives. The invention also relates to methods for preparing novel phosphorus-containing cellulose esters and to their use as flame retardants for plastics.

A liquid composition contains a cellulosic material constituted by a material containing at least one of cellulose and a cellulose derivative, and an ionic liquid having a functional group with reactivity. It is preferred that the ionic liquid has an imidazolium salt structure. It is also preferred that the functional group with reactivity contains a carbon-carbon double bond.

A liquid composition contains a cellulosic material constituted by a material containing at least one of cellulose and a cellulose derivative, and an ionic liquid having a functional group with reactivity. It is preferred that the ionic liquid has an imidazolium salt structure. It is also preferred that the functional group with reactivity contains a carbon-carbon double bond.

Provided are a composite for cellulose fiber dispersion that can inexpensively and sufficiently disperse cellulose fibers, particularly nanocellulose, in a hydrophobic resin and a cellulose fiber composition containing the composite. A composite for cellulose fiber dispersion according to the present invention has a structure in which a vinyl polymer is grafted to a cellulose derivative. A cellulose fiber composition according to the present invention contains the composite and cellulose fibers and more specifically also contains an organic solvent, a resin precursor, or a resin.

Provided are a composite for cellulose fiber dispersion that can inexpensively and sufficiently disperse cellulose fibers, particularly nanocellulose, in a hydrophobic resin and a cellulose fiber composition containing the composite. A composite for cellulose fiber dispersion according to the present invention has a structure in which a vinyl polymer is grafted to a cellulose derivative. A cellulose fiber composition according to the present invention contains the composite and cellulose fibers and more specifically also contains an organic solvent, a resin precursor, or a resin.

Provided is a method for producing a composition for forming a gas separation membrane active layer, the method including: obtaining a first reactant by allowing a cellulose-based compound and an acid substituted with fluorine to react; and adding dropwise an acid anhydride substituted with fluorine to the first reactant at a temperature higher than room temperature. Also provided is a composition for forming a gas separation membrane active layer.

The present disclosure provides a cellulose derivative which has excellent storage stability and can selectively adsorb a valuable metal and a toxic metal. The cellulose derivative of the present disclosure has a repeating unit represented by Formula (I) below. In Formula (I) below. R.sup.as are identical or different and are a hydrogen atom or a group represented by Formula (a) below. In Formula (a) below, ring Z represents a heterocycle containing a nitrogen atom as a heteroatom, and R.sup.1 represents a single bond or an alkylene group having from 1 to 10 carbons. Four R.sup.2s are identical or different, and each represent an alkyl group having from 1 to 10 carbons. At least one of all the R.sup.as included in the cellulose derivative is a group represented by Formula (a) below.

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Disclosed are cellulose-based 5 flexible aerogels and xerogels containing bacterial cellulose nanorods, ribbons, fibers, and the like, wherein the gels have tunable optical, heat transfer, and stiffness properties. Further disclosed are highly transparent and flexible cellulose nanofiber-polysiloxane composite aerogels featuring enhanced mechanical robustness, tunable optical anisotropy, and low thermal conductivity.

Provided is a method for producing a composition for forming a gas separation membrane active layer, the method including: obtaining a first reactant by allowing a cellulose-based compound and an acid substituted with fluorine to react; and adding dropwise an acid anhydride substituted with fluorine to the first reactant at a temperature higher than room temperature. Also provided is a composition for forming a gas separation membrane active layer.