Multifunctional Magnetic Hydrogels Fabricated by Iron Oxide Nanoparticles Mediated Radical Polymerization

Enzymatic polymerization is widely used in the fabrication of hydrogels due to its high biocompatibility and controllability. However, it usually suffers from the destabilization of enzymes under hard conditions and the requirement of diketones substrates to fulfill radical polymerization. Herein, multifunctional magnetic hydrogels (MMHs) are constructed in the presence of hydrogen peroxide (H2O2) by iron oxide nanoparticle (Fe3O4 NP)-mediated radical polymerization. In comparison with the natural enzyme initiation systems, a Fe3O4 NPs/H2O2 system can initiate the polymerization of poly(ethylene glycol) diacrylate instantaneously at ambient temperature without the substrate and can display higher catalytic activity under acidic conditions. The resultant magnetic composites have multifunctionality of the integration of magnetism, superwetting, and photothermal responsiveness, as well as the catalytic activity of a mimic enzyme, achieving effective rapid separation of oil-in-water emulsions and fast degradation of organic dye with good recyclability.