Process for the preparation of modified polysaccharides having improved absorbent properties
AssigneeKimberly-Clark Corporation
InventorJian Qin
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Abstract
Disclosed is a method for producing a surface-crosslinked, modified polysaccharide having improved absorption properties. The method involves forming a mixture of water and a crosslinking agent, adding a generally water-soluble, modified polysaccharide to said mixture wherein the surface of the polysaccharide becomes crosslinked, and drying the modified polysaccharide. Also described is a surface-crosslinked, modified polysaccharide having improved absorption properties.
Claims21
A method for producing a crosslinked, modified polysaccharide, the method comprising the following steps:
- forming a mixture comprising water and a crosslinking agent wherein the crosslinking agent is water soluble and comprises a compound having at least two functional groups or functionalities capable of reacting in an aqueous solution with a carboxyl, hydroxyl, or amino group of a modified polysaccharide;
- adding to said mixture an amount of a water-soluble, modified polysaccharide, that is free from a substantial degree of crosslinking, such that the weight ratio of water-soluble, modified polysaccharide to water in said mixture is from about 1:2 to about 1:40, wherein said water-soluble modified polysaccharide becomes crosslinked and wherein said crosslinked modified polysaccharide comprises a substantially non-crosslinked, water-soluble, modified polysaccharide core and a crosslinked, water-insoluble modified polysaccharide shell at least partially surrounding said core, said crosslinked modified polysaccharide being swellable in said mixture;
- and
- drying said crosslinked modified polysaccharide, wherein said crosslinked, modified polysaccharide has an initial Absorbency Under Load at least about 200 percent greater than said water-soluble, modified polysaccharide.
A method for forming a crosslinked, carboxyalkyl polysaccharide, the method comprising the following steps:
- forming a mixture comprising at least about 75 weight percent water and an amount of a crosslinking agent effective to provide a desired degree of crosslinking, wherein the crosslinking agent is water soluble and comprises a compound having at least two functional groups or functionalities capable of reacting in an aqueous solution with a carboxyl, hydroxyl, or amino group of a modified polysaccharide;
- adding to said mixture an amount of a water-soluble, carboxyalkyl polysaccharide, that is free from a substantial degree of crosslinking, said water-soluble, carboxyalkyl polysaccharide being added to said mixture such that the weight ratio of carboxyalkyl polysaccharide to water is from about 1:2 to about 1:40, wherein said carboxyalkyl polysaccharide becomes crosslinked and wherein said crosslinked carboxyalkyl polysaccharide comprises a substantially non-crosslinked, water-soluble, carboxyalkyl polysaccharide core and a crosslinked, water-insoluble carboxyalkyl polysaccharide shell at least partially surrounding said core, said crosslinked carboxyalkyl polysaccharide being swellable in said mixture;
- and
- drying said crosslinked carboxyalkyl polysaccharide, wherein said crosslinked, carboxyalkyl polysaccharide has an initial Absorbency Under Load at least about 200 percent greater than said water-soluble, carboxyalkyl polysaccharide.
Dependencies are inferred from the claim text.