Magnetic iron oxide nanoparticles as long wavelength photoinitiators for free radical polymerization

Iron oxide nanoparticles (Fe₃O₄ NPs) capped with lauric acid agents were synthesized and their photocatalytic activity was investigated in free radical photopolymerization of vinyl monomers. These NPs were able to release charge carriers (electron–hole pairs) upon photoexcitation through which the capping agents or an additional amine co-initiator acting as the hole acceptor underwent oxidation to eventually form the initiating radicals. In lauric acid coated Fe₃O₄ NPs, electron transfer followed by a decarboxylation process accounts for the initiation.