Stabilization of electrophoretically adhered gel-interfaces to construct multi-layered hydrogels

The stabilization of electrophoretically adhered hydrogels by rearranging the surface interdigitating chain segments across the interface was investigated for the preparation of adhered multilayer hydrogels. Two hydrogels were adhered by electrophoresis with the formation of a polyion complex and the entanglement of the linear chains with networks. We then investigated the relationship between the swelling ratios of the gels and the molecular weight of the polyelectrolyte inside the gels for the electrophoretic adhesion of hydrogels. A deswelling/re-swelling process of the adhered hydrogels induced resistance against bending stress, ionic strength, and inverse voltage because of a rearrangement of the surface interdigitating chain segments across the interface. Therefore, adhered (PAAm/PNIPAAm)(13)PAAm multi-layer hydrogels, which showed uniaxial movement in response to temperature were prepared.