Patent ID: 8357728

Claim:
A method for producing a water-soluble porous, polymeric material comprising the steps of: (a) providing a C/W emulsion comprising an aqueous phase, a matrix building material in the form of a water-soluble polymeric material, a surfactant and a liquid CO 2 phase; (b) at least partially freezing the aqueous phase; (c) gasifying CO 2 from the liquid CO 2 phase to produce an intermediate porous material; (d) venting the gasified CO 2 from the intermediate porous material; and (e) freeze drying the intermediate porous material at least substantially to remove the aqueous phase and to form the water-soluble porous material; wherein said water-soluble polymeric material is one or more chosen from the group consisting of water-soluble polysaccharides and water-soluble vinyl polymers, and is substantially free of cross-linking such that said water-soluble porous material is able to substantially fully dissolve in water at 20° C.