Patent ID: 8501214

Claim:
A hydrophilic foam comprising a polyurethane matrix having a plurality of cells, wherein the hydrophilic foam is prepared from a composition comprising: (1) 1 part by weight of water, wherein the water is a sole blowing agent of the composition; (2) at least one hydrophilic polyol, wherein the hydrophilic polyol is about 35-40 parts by weight of polyoxyethylene polyoxypropylene glyceryl ether, or a mixture of about 10-12 parts by weights of polyoxypropylene glyceryl ether and about 25-28 parts by weight of polyoxyethylene polyoxypropylene glyceryl ether; (3) an isocyanate in an amount of about 10 to 15 parts by weight, wherein the isocyanate is 4,4′-diphenylmethane diisocyanate; (4) a catalyst in an amount of about 0.01 to 0.1 part by weight, wherein the catalyst is N-ethyl morpholine; 5) a chain extender in an amount of about 0.05 to 0.1 part by weight, wherein the chain extender is diethanolamine; and (6) a foam stabilizer in an amount of about 0.1 to 1 part by weight, wherein the foam stabilizer is a silicone surfactant; whereby the cells are capable of retaining water in an amount of about 10-20 grams of water per gram of the hydrophilic foam and retaining gel in an amount of about 1-25 grams of gel per gram of the hydrophilic foam.