The present invention provides a method of producing a polymer hydrogel comprising the steps of: (1) preparing an aqueous solution of a water soluble polysaccharide derivative and a polycarboxylic acid; (2) optionally agitating the solution, for example, by stirring; (3) isolating a polysaccharide derivative/polycarboxylic acid composite from the solution; and (4) heating the polysaccharide derivative/polycarboxylic acid composite at a temperature of at least about 80° C., thereby cross-linking the polysaccharide with the polycarboxylic acid. The invention also provides polymer hydrogels produced by the methods of the invention.

The present invention provides a method of producing a polymer hydrogel comprising the steps of: (1) preparing an aqueous solution of a water soluble polysaccharide derivative and a polycarboxylic acid; (2) optionally agitating the solution, for example, by stirring; (3) isolating a polysaccharide derivative/polycarboxylic acid composite from the solution; and (4) heating the polysaccharide derivative/polycarboxylic acid composite at a temperature of at least about 80° C., thereby cross-linking the polysaccharide with the polycarboxylic acid. The invention also provides polymer hydrogels produced by the methods of the invention.

Disclosed are compounds, in particular based on polysaccharides, that are adsorbed on a cellulosic material, and relates in particular to the application of such compounds as reinforcing agent for cellulosic materials, in the wet and/or dry state. The compounds include a combination of at least one polysaccharide adsorbed on a cellulosic material, the polysaccharide including at least two different monosaccharide units, forming first and second monosaccharide units, the second monosaccharide units being branched on a chain including at least the first monosaccharide units, at least some of the second monosaccharide units being non-cyclic and bearing aldehyde functions, the aldehyde functions possibly forming hemiacetal functions with hydroxy functions of the cellulosic material.

The HIGH ALPHA AND HIGH INTRINSIC VISCOSITY PULP PRODUCTION APPARATUSES, METHODS AND SYSTEMS (hereinafter “HIGH-A HIGH-IV PULP PRODUCTION”) disclosed herein provide for pulp processing used in connection with Kraft Processes (KP) or Pre Hydrolysis Kraft Processes (PHKP), embodiments employing a Cold Caustic Extraction (CCE) stage and/or appropriate washing and bleaching stages, resulting in pulp with high Intrinsic Viscosity (IV) and high purity, such as may be as determined by alpha cellulose content, and adequate brightness for use downstream in applications such as high tensile regenerated cellulose and ether applications, or other applications employing high IV pulp with significant purity (e.g., alpha cellulose>92%).

The HIGH ALPHA AND HIGH INTRINSIC VISCOSITY PULP PRODUCTION APPARATUSES, METHODS AND SYSTEMS (hereinafter “HIGH-A HIGH-IV PULP PRODUCTION”) disclosed herein provide for pulp processing used in connection with Kraft Processes (KP) or Pre Hydrolysis Kraft Processes (PHKP), embodiments employing a Cold Caustic Extraction (CCE) stage and/or appropriate washing and bleaching stages, resulting in pulp with high Intrinsic Viscosity (IV) and high purity, such as may be as determined by alpha cellulose content, and adequate brightness for use downstream in applications such as high tensile regenerated cellulose and ether applications, or other applications employing high IV pulp with significant purity (e.g., alpha cellulose>92%).

A rubber composition containing a rubber and modified cellulose fibers, wherein one or more substituents selected from substituents represented by the following general formulas (1) and (2): —CH.sub.2—CH(OH)—R.sub.1 (1), —CH.sub.2—CH(OH)—CH.sub.2—(OA).sub.n—O—R.sub.1 (2), wherein each R.sub.1 in the general formulas (1) and (2) is independently a linear or branched alkyl group having 3 or more carbon atoms and 30 or less carbon atoms; n in the general formula (2) is a number of 0 or more and 50 or less; and A is a linear or branched, divalent saturated hydrocarbon group having 1 or more carbon atoms and 6 or less carbon atoms are bonded to cellulose fibers via an ether bond, wherein the modified cellulose fibers have a cellulose I crystal structure. The rubber composition of the present invention can be suitably used for machine tool parts, household electric appliance parts, automobile parts, and the like.

A rubber composition containing a rubber and modified cellulose fibers, wherein one or more substituents selected from substituents represented by the following general formulas (1) and (2): —CH.sub.2—CH(OH)—R.sub.1 (1), —CH.sub.2—CH(OH)—CH.sub.2—(OA).sub.n—O—R.sub.1 (2), wherein each R.sub.1 in the general formulas (1) and (2) is independently a linear or branched alkyl group having 3 or more carbon atoms and 30 or less carbon atoms; n in the general formula (2) is a number of 0 or more and 50 or less; and A is a linear or branched, divalent saturated hydrocarbon group having 1 or more carbon atoms and 6 or less carbon atoms are bonded to cellulose fibers via an ether bond, wherein the modified cellulose fibers have a cellulose I crystal structure. The rubber composition of the present invention can be suitably used for machine tool parts, household electric appliance parts, automobile parts, and the like.

Provided is a method for producing hydroxypropyl methyl cellulose (HPMC) having high hydroxypropoxy content, low ash content, and low insoluble fiber content. More specifically, provided is a method for producing HPMC having a methoxy degree of substitution of from 1.4 to 2.2 and a hydroxypropoxy molar substitution of from 0.5 to 1.0, including steps of: bringing sheet-like or chip-like pulp into contact with an alkali metal hydroxide solution to obtain a reaction product mixture containing alkali cellulose, removing a liquid portion from the reaction product mixture to obtain the alkali cellulose, reacting the alkali cellulose with an etherifying agent to obtain a crude HPMC, disintegrating the crude HPMC into a disintegrated crude HPMC, dispersing the disintegrated crude HPMC in water to obtain a slurry, filtering the slurry to obtain a cake, and washing the cake.

Provided is a method for producing hydroxypropyl methyl cellulose (HPMC) having high hydroxypropoxy content, low ash content, and low insoluble fiber content. More specifically, provided is a method for producing HPMC having a methoxy degree of substitution of from 1.4 to 2.2 and a hydroxypropoxy molar substitution of from 0.5 to 1.0, including steps of: bringing sheet-like or chip-like pulp into contact with an alkali metal hydroxide solution to obtain a reaction product mixture containing alkali cellulose, removing a liquid portion from the reaction product mixture to obtain the alkali cellulose, reacting the alkali cellulose with an etherifying agent to obtain a crude HPMC, disintegrating the crude HPMC into a disintegrated crude HPMC, dispersing the disintegrated crude HPMC in water to obtain a slurry, filtering the slurry to obtain a cake, and washing the cake.

Phosphoethanolamine cellulose and methods of making and using it are disclosed. In particular, the invention relates to a method of producing a phosphoethanolamine cellulose biosynthetically using a BcsG phosphoethanolamine transferase for cellulose modification. Recombinant constructs encoding BcsG are described, including constructs encoding BcsG by itself or in combination with BcsE and BcsF, which increase the extent of cellulose modification and the amount of modified cellulose produced. Production of phosphoethanolamine cellulose in cell culture and derivatization of phosphoethanolamine cellulose are also described.