Patent ID: 7485670

Claim:
An injectable thetagel solution for injection into a body space, wherein the injectable solution is obtained by a process comprising the steps of: dissolving polyvinyl alcohol (PVA) molecules in a first solution to form a PVA solution, wherein the first solution has a Flory interaction parameter (chi value) that is not sufficient for gelation; contacting the PVA solution with a second solution in a controlled manner, wherein after the contacting the combination of both solutions has a Flory interaction parameter (chi value) that is sufficient for gelation, and thereby forms an injectable thetagel solution; and maintaining for a period of time the injectable thetagel solution at a temperature such that it is in a workable state, wherein the injectable thetagel solution can be injected into a body space, and therein gel in situ after the injection to form in the body space a polymer hydrogel that has physical crosslinks between PVA molecules, wherein the polymer hydrogel is formed without chemical crosslinkers, irradiation or thermal cycling, and wherein the polymer hydrogel can fill the body space.