Expanding-contracting hydrogel composite and process for preparation thereof

Abstract From the Canadian patent

A process is provided for the preparation of expanding-contracting hydrogel composites which process comprises the steps of adding solid particles of a polyelectrolyte to a polyvinyl alcohol solution and subjecting the mixture to a low temperature treatment to cause gelation of the polyvinyl alcohol with the polyelectrolyte dispersed as a heterogeneous phase (i.e. solid particles) within the polyvinyl alcohol gel. Hydrogel composites made by the process exhibit high strength and a capacity to expand and contract over a wide range with changes in environment. These composites have utility as mechanical devices such as artificial muscle or other devices which are capable of converting …