Abstract: A supported polyionic hydrogel is prepared by impregnating a support matel with a solution of anionic polysaccharide and a solution of cationic polysaccharide where the anionic polysaccharide and cationic polysaccharide react with each other to form a polyionic hydrogel impregnated in the support material. The hydrogel may be dried such as by lyophilization. Preferably, the anionic polysaccharide is xanthan, dicarboxystarch or dicarboxycellulose and the cationic polysaccharide is chitosan. Especially preferred is a polyionic hydrogel formed from xanthan and chitosan. A paper material or a textile material can be used as the support material. A dry supported polyionic hydrogel can be formed as a bandage without active material incorporated therein. The supported polyionic hydrogel may be formed containing a biologically active material by having the active material in either polysaccharide solution or in another solution impregnated into the support material.

Abstract: The invention provides a dry, disposable, polymeric product having sustained-release anti-microbial activity, the product consisting essentially of a polymeric material selected from the group consisting of fibers, fabrics, sheets, films and other stable woven, non-woven and knitted materials prepared from natural, man-made and synthetic polymers and an amine salt anti-microbial agent, the anti-microbial agent being incorporated in the polymeric material without an intermediary adhesive, carrier or linking agent and being releasable therefrom in anti-microbially effective amounts for a period of at least three days upon the product being brought into contact with a moist surface.

Abstract: A supported polyionic hydrogel containing biologically active material is epared by impregnating into a porous support material a solution of anionic polysaccharide, a solution of cationic polysaccharide and a biologically active material. The anionic polysaccharide and the cationic polysaccharide react with each other to form a hydrogel containing the biologically active material. The hydrogel may be dried such as by lyophilization. The biologically active material can be in either polysaccharide solution or in another solution impregnated into the porous support material. A paper material or a textile material may be used as the porous support material. Preferably, the anionic polysaccharide is xanthan, dicarboxystarch or dicarboxycellulose and the cationic polysaccharide is chitosan. Especially preferred is a hydrogel formed from xanthan and chitosan.

Abstract: A method of improving the sorption capacity of a substantially hydrophobic, thermoplastic polymer, which comprises introducing into the polymer a halogen by contacting the polymer with a solution containing the halogen under conditions which avoid chemical reaction of the halogen with the polymer, separating the free halogen-containing polymer from the solution, and contacting the polymer with a reagent which pervades the polymer and reacts with the free halogen contained therein so as to produce a gas as one of the reaction products. The product polymers have increased sorption capacity and improved dyeability and are capable of sorbing and retaining useful substances such as medicaments, pesticides and perfumes.