Supramolecular Superparamagnetic Nanocomposites Based on a Magnetite-Filled Unentangled Terpyridine-Functionalized Polymer

摘要

Beyond their usual combination with metal ions, we show that terpyridine (TPy)-functionalized polymers can be associated with inorganic nanoparticles to form transient networks via supramolecular bonds. These interactions are first evidenced by differential scanning calorimetry where a growing fraction in magnetite (Fe3O4) nanoparticles is seen to shift up and broaden significantly the glass transition of PnBA-TPy (+8 degrees C) whereas no effect is observed in the corresponding pure PnBA matrix. The formation of an organic-inorganic physical network is then revealed by rheological measurements highlighting the extra friction caused by the TPy groups at longer timescales. Because they are based on unentangled polymers, such nanocomposites present, in addition, the great advantage to switch rapidly from the solid to the liquid state when submitted to an oscillatory magnetic field. Under this so-called induction heating, the physical network is dismantled remotely from the inside, making this class of materials promising candidates for the design of responsive rubbers.