Surface modification of magnetite nanoparticles with poly(tert-butyl acrylate) via atom transfer radical polymerization

Abstract

Magnetic nanoparticles (MNPs) grafted with poly(tert-butyl acrylate) (poly(t-BA))via surface-initiated atom transfer radical polymerization (ATRP) is herein presented. MNPswere synthesized via a thermal decomposition reaction of iron (III) acetylacetonate in benzylalcohol to obtain narrow-size distribution particles. Magnetite nanoparticles werecharacterized by X-ray diffraction (XRD) technique. BTPAm was synthesized from reactionbetween 3-aminopropyl triethoxysilane (APS) and 2-bromoisobutyryl bromide (BIBB) thatused for ATRP. Firstly, The initiator was covalently bonded onto the MNP surfaces to createactive initiating sites, followed by ATRP of t-BA monomers to obtain poly(t-BA)-graftedMNPs. Nuclear magnetic resonance (NMR) was used to confirm chemical structure ofBTPAm. Fourier transform infrared spectroscopy (FTIR) was used to monitor the reactionprogress in each step of the syntheses. Transmission electron micrographs (TEM) revealedthat the particle size was about 8 nm in diameter without significant aggregation during thepreparation process. The particle size was not affected owing to the surface modificationprocedure.