Superabsorbent foams and method for producing the same

A microporous, open-celled foam produced by the method comprising the steps of:

• (a) mixing hydroxyethyl cellulose (HEC), water and a phase-separation enhancer to form a substantially homogeneous, single-phase solution, wherein said phase-separation enhancer is chosen from the group consisting of salts, water-soluble organic solvents, and combinations of salts and water-soluble organic solvents;
• (b) inducing crosslinking of said HEC by adding a suitable crosslinking agent to said single-phase solution;
• (c) inducing phase separation of said single-phase solution into a polymer-concentrated phase and a polymer-dilute phase, wherein said phase separation is induced by increasing the temperature of said single-phase solution to above the lower consolute solution temperature of said single-phase solution;
• (d) permitting said crosslinkin to continue, so that said HEC will crosslink in said concentrated phase for a predetermined period of time during said phase separation to thereby form a microporous material;
• and
• (e) drying said microporous material to produce said microporous foam.

An absorbent microporous foam capable of absorbing at least ten times its dry weight in fluid comprising a cross-linked polymer having interconnected fluid cells distributed throughout the mass of said foam, wherein said fluid cells have a diameter of between about 0.1 and about 100 .mu.m, and wherein said cross-linked polymer is selected from the group consisting of hydroxypropyl dextran;

• hydroxypropyl guar;
• hydropropyl starch;
• hydroxypropyl cellulose, hydroxyethyl cellulose;
• methyl cellulose;
• hydropropyl methyl cellulose;
• ethylhydroxyethyl cellulose;
• and mixtures thereof.