Acrylate monomer polymerization triggered by iron oxide magnetic nanoparticles and catechol containing microgels

•Novel catalytic system consisted of iron oxide magnetic nanoparticle and catechol.•Catechol-generated ROS further converted to hydroxyl radical by iron.•Initiates polymerization of wide ranges of monomers in an oxygenated solution.•Magnetic, bilayer hydrogels were formed with improved mechanical property.