Synthesis and characterization of nanostructured PS-b-P4VP/Fe2O3 thin films with magnetic properties prepared by solvent vapor annealing

Abstract

In this work hybrid organic/inorganic nanocomposites with magnetic properties, based on a PS-b-P4VP block copolymer and Fe₂O₃ maghemite nanoparticles have been prepared. The nanoparticles were surface modified with PS brushes by the grafting through method. The morphology of the neat block copolymer and nanocomposites was analyzed by AFM. For nanostructuring, thin films were annealed under dioxane vapors, a selective solvent for the PS block. The morphology of the neat copolymer thin films changed from hexagonal to strips with exposure time. The addition of the nanoparticles also modified the morphology of the nanocomposites, especially the higher nanoparticle contents. For all cases the nanoparticles were selectively dispersed into PS domains. Moreover, magnetic characterization by VSM and SQUID has demonstrated that the magnetic properties of the nanoparticles have been transferred to the nanocomposites.