HYDROGEL SYNTHESIS

The invention provides a method for preparing a hydrogel from a hydrophilic polymer having one or more functional groups which are capable of co-reacting in a condensation reaction which method comprises the steps of: (i) preparing a solution of the polymer; (ii) heating the solution to a temperature sufficient for the condensation reaction to take place for a period of time sufficient for the hydrogel to cross-link wherein where the hydrophilic polymer comprises a first and a second hydrophilic polymer, step (i) comprises a step of mixing the hydrophilic polymers to prepare a homogeneous intimate mixture of the polymers; and wherein the heating step (ii) is carried out at a pressure greater than atmospheric pressure. The method of the invention is advantageous because it is relatively low cost, it is a safer procedure with less health & safety concerns, it is carried out in a liquid state and is not limited by film thickness.