Reversible Hydrogels with Switchable Diffusive Permeability

Hydrogels are polymer networks swollen in water that characterized by soft mechanics and high permeability. This makes them good candidates for separation membrane technologies. The diffusion is controlled the mesh size of network, this can be made tunable through introduction thermoresponsive polymers. However, still a developing field. To contribute to development, dual dynamic network formed composed four-arm polyethylene glycol precursors which each arm functionalized with both terpyridine moiety capable forming reversible metal–ligand complexes along branches poly(N-isopropylacrylamide) (pNIPAAm), switched between expanded collapsed states therewith offers path switching microscopic gel-network size, macroscopic gel elasticity. dually sensitive hydrogel has capability doubling its elastic modulus when going above lower critical solution temperature (LCST) pNIPAAm. In addition, diffusive permeability upon change temperature, whereby diffusants trapped LCST Moreover, it possible disassemble reform pH. With that, potential application as switchable membrane.