Aqueous dispersions of iron oxide nanoparticles with linear-dendritic copolymers

In this study, we report an efficient synthetic method of water dispersible magnetite nanoparticles having oleic acid and poly(ethylene glycol)–poly(2-ethyl-2-oxazoline)–poly(ɛ-caprolactone) amphiphilic copolymer as magnetite nanoparticle dispersants. The Fe3O4 nanoparticles were prepared by chemical coprecipitation and had bilayer surface with hydrophobic inner poly(ɛ-caprolactone) layer and hydrophilic corona poly(ethylene glycol)–poly(2-ethyl-2-oxazoline) blocks. Moreover, role of time of ultrasonicating treatment, on percent of magnetite in the complex and its magnetic properties were investigated. Transmission electron microscopy (TEM) showed the average particle size of about 10–12 nm in diameter for nanoparticles.