Abstract:
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.
Abstract:
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.
Abstract:
Provided are compounds and methods for modifying a material to change properties of the material, as well as a variety of products obtained using the methods. In one embodiment, a material comprising one or more modifiable functional groups is reacted with an activated hydrophobic acyl group in the presence of a hindered base, thereby to covalently attach the hydrophobic acyl group to the modifiable functional groups on the material. The material which is modified may be, for example, a carbohydrate, and the modifiable functional groups on the material may be hydroxyls. For example, materials such as cellulose may be modified by reacting it with an acid chloride or acid anhydride including a hydrophobic acyl group, in the presence of a hindered base, such as tripentylamine, to attach the hydrophobic acyl groups to the hydroxyls on the cellulose, thereby to increase the hydrophobicity of the cellulose. The methods and compounds disclosed herein may be used to modify materials to improve properties such as resistance, grease repellency, soil resistance and permanent press properties.
Abstract:
The present invention relates to a cellulose derivative having biodegradability, recycling properties, excellent mechanical strength and mold processability. The cellulose derivative is a product of a monosaccharide derivative or oligosaccharide derivative and cellulose. The monosaccharide derivative or oligosaccharide derivative is a copolymer of a saccharide and dicarboxylic acid.
Abstract:
Provided are compounds and methods for modifying a material to change properties of the material, as well as a variety of products obtained using the methods. The material which is modified may be, for example, a carbohydrate, and the modifiable functional groups on the material may be hydroxyls. Multifunctional molecules for use in modifying the surfaces of materials such as textile fibers, yams and other fabrics made of or, including cotton, wool and nylon, are provided. The multifunctional molecules can include hydrophobic regions and/or hydrophilic regions. The multifunctional molecules also may include binding functional groups that permit either non-covalent or covalent binding to the material being modified, thus permitting the multifunctional molecule to form a non-covalent or covalent coating on the material. The methods and compounds disclosed herein may be used to modify materials to improve properties such as resistance, grease repellency, soil resistance permanent press properties, and quickness of drying.
Abstract:
The present invention relates to a cellulose derivative having biodegradability, recycling properties, excellent mechanical strength and mold processability. The cellulose derivative is a product of a monosaccharide derivative or oligosaccharide derivative and cellulose. The monosaccharide derivative or oligosaccharide derivative is a copolymer of a saccharide and dicarboxylic acid.
Abstract:
Novel cellulose ester derivatives having good solubility which are useful for coating agent, thickening agent, protective colloid, etc.; and a method for the preparation of said cellulose ester derivatives wherein cellulose is reacted with a specific lactone such as glycolide, lactide or .epsilon.-caprolactone in a solvent and in the presence of a catalyst for esterification.
Abstract:
ACID PHTHALATE OF CELLULOSE ETHERS REPRESENTED BY THE GENERAL FORMULA:
R1MR2NA
WHERE R1 IS A HYDROXYALKYL GROUP OF 3 OR 4 CARBON ATOMS, R2, HYDROGEN OR AN ALKYL GROUP OF 1 OR 2 CARBON ATOMS, M AND N ARE POSITIVE INTEGERS, AND A IS RESIDUAL CELLULOSE STRUCTURE WHICH ETHERS ARE READILY SOLUBLE IN WEAK ALKALINE SOLUTION, BESIDES POSSESSING HIGH SOLUBILITY IN ORGANIC SOLVENTS AND EXCELLENT RESISTANCE TO WATER; THEY ARE USEFUL AS ENTERIC COATINGS, AND DRUGS COATED WITH THEM CAN STAND LONG STORAGE AND ARE READILY SOLUBLE UPON PASSING INTO THE INTESTINES, THEREBY ENHANCING THE EFFECT OF THE DRUGS.