A reactive extrusion process for the production of substituted polysaccharides, in particular, cellulose acetate, starch acetate, carboxymethyl cellulose, and carboxymethyl starch.

A method for manufacturing a modified hydroxyethyl starch carrying a heptonic acid residue on at least one of its termini. Within this method, the following steps are carried out: a) dissolving hydroxyethyl starch in water, b) adjusting the pH value to a value of 8.0 to 10.0, c) adding a cyanide compound to the hydroxyethyl starch solution, heating the solution to a temperature of 80 to 99 C. and keeping it at this temperature for a first time period, and d) adjusting the pH value to a value of 2.0 to 4.0, bringing the solution to a temperature of 50 to 90 C. and keeping it at this temperature for a second time period.

A method for manufacturing a modified hydroxyethyl starch carrying a heptonic acid residue on at least one of its termini. Within this method, the following steps are carried out: a) dissolving hydroxyethyl starch in water, b) adjusting the pH value to a value of 8.0 to 10.0, c) adding a cyanide compound to the hydroxyethyl starch solution, heating the solution to a temperature of 80 to 99 C. and keeping it at this temperature for a first time period, and d) adjusting the pH value to a value of 2.0 to 4.0, bringing the solution to a temperature of 50 to 90 C. and keeping it at this temperature for a second time period.

Disclosed is a cold-water soluble starch and a process for preparing same. Generally, the process comprises providing a hydroxyalkyl starch and applying a shearing force to the starch in an extruder in the presence of moisture, the force and the moisture each being sufficient to gelatinize at least substantially all of the granules of the starch to thereby form a sheared starch. The starch is heated to its gelatinization temperature after the starch has passed partially through the barrel of the extruder, with the moisture being maintained at a level sufficiently high to allow gelatinization but sufficiency low to protect the starch from becoming too sticky to extrude. The extruded starch product thus formed may be used in connection with a number of film-forming, coating, and other applications.

Disclosed is a cold-water soluble starch and a process for preparing same. Generally, the process comprises providing a hydroxyalkyl starch and applying a shearing force to the starch in an extruder in the presence of moisture, the force and the moisture each being sufficient to gelatinize at least substantially all of the granules of the starch to thereby form a sheared starch. The starch is heated to its gelatinization temperature after the starch has passed partially through the barrel of the extruder, with the moisture being maintained at a level sufficiently high to allow gelatinization but sufficiency low to protect the starch from becoming too sticky to extrude. The extruded starch product thus formed may be used in connection with a number of film-forming, coating, and other applications.

A process for modifying starch is described. The process can be used as an alternative to conventional starch modification processes, such as substitution and crosslinking. The process and resulting product can reduce, substantially reduce, substantially eliminate or eliminate the sodium level typically associated with conventionally modified starch products.

A process for modifying starch is described. The process can be used as an alternative to conventional starch modification processes, such as substitution and crosslinking. The process and resulting product can reduce, substantially reduce, substantially eliminate or eliminate the sodium level typically associated with conventionally modified starch products.

The present document describes a powder composition comprising a functionalized starch having a single helix V-structure and having a degree of substitution of at least 0.25, and a bioactive agent, forming an inclusion complex with said functionalized starch, where the bioactive agent is within the helix V-structure of the functionalized starch having a single helix V-structure. Also described are the functionalized starch having a single helix V-structure and having a degree of substitution of at least 0.25, methods of making the same and methods of using the same to manufacture the powder composition.

A method for the synthesis of alkyl -carboxy(hydroxyethyl) polysaccharides is described. The method includes methylating or ethylating a polysaccharide or providing a methylated or ethylated polysaccharide, hydroxyethylating the methylated or ethylated polysaccharide, and oxidizing the hydroxyethylated polysaccharide to form the -carboxy(hydroxyethyl) polysaccharide. A method for the synthesis of oxidized polysaccharides is also described. The method includes hydroxypropylating a polysaccharide and oxidizing the hydroxypropylated polysaccharides. A method for the production of a solid capable of forming a hydrogel is also described. The method includes combining a first solution comprising an oxidized oligo(hydroxypropyl) polysaccharide bearing one or more ketone groups with a second solution comprising an amine substituted polysaccharide to form a third solution, and removing solvent from the third solution to form the solid, or adding an additional solvent to the third solution to precipitate the solid. Novel polysaccharides and hydrogels prepared according to these methods are also described.

A method for the synthesis of alkyl -carboxy(hydroxyethyl) polysaccharides is described. The method includes methylating or ethylating a polysaccharide or providing a methylated or ethylated polysaccharide, hydroxyethylating the methylated or ethylated polysaccharide, and oxidizing the hydroxyethylated polysaccharide to form the -carboxy(hydroxyethyl) polysaccharide. A method for the synthesis of oxidized polysaccharides is also described. The method includes hydroxypropylating a polysaccharide and oxidizing the hydroxypropylated polysaccharides. A method for the production of a solid capable of forming a hydrogel is also described. The method includes combining a first solution comprising an oxidized oligo(hydroxypropyl) polysaccharide bearing one or more ketone groups with a second solution comprising an amine substituted polysaccharide to form a third solution, and removing solvent from the third solution to form the solid, or adding an additional solvent to the third solution to precipitate the solid. Novel polysaccharides and hydrogels prepared according to these methods are also described.