Magnetic Organosilica Nanoparticles for Localized Polymer Surface Modification

Abstract Magnetic organosilica nanoparticles are synthesized by grafting MPB‐POSS/MMA‐based block copolymers from magnetic iron nanoparticles via surface‐initiated ATRP. The hybrid nanoparticles consist of a magnetic iron core and a PMMA/POSS composite shell. A small amount of the nanoparticles is added as “smart additive” in casting PMMA sheets for localized surface modification. It is demonstrated that the particles are readily brought to the surface of the cast piece by applying a magnet field to the molding. At 1 wt% loading, the sample has a 50‐time higher particle content in a 100 µm‐thick surface layer than in the bulk. The indentation hardness of the modified surface is increased by 30%. magnified image