Novel carboxyl functional spherical electromagnetic polypyrrole nanocomposite polymer particles with good magnetic and conducting properties

Magnetic conducting nanoparticles with reactive functional groups are attractive materials for applications in electromagnetic interference shielding, magneto-optical storage, biomedical sensing, gas and humidity sensors, flexible electronics etc. The objective of this work was to prepare carboxyl functionalized polypyrrole (PPy) nanocomposite particles having good magnetic properties. Electromagnetic PPy nanostructures, abbreviated as PPy/γ-Fe2O3, were first prepared by a chemical one-step method. In this reaction process FeCl3 is used as an oxidant for the polymerization of pyrrole and as a source of Fe3+ for the formation of γ-Fe2O3. The formation of γ-Fe2O3 is also aided by the initial presence of Fe2+, and p-toluenesulfonic acid (p-TSA) acted as a dopant. The effects of different stabilizers on the stability and morphology of PPy/γ-Fe2O3 particles were evaluated. The presence of citric acid/sodium dodecyl sulfate during chemical oxidative polymerization produced a relatively stable PPy/γ-Fe2O3 colloidal emulsion. PPy/γ-Fe2O3/poly(methylmethacrylate-methacrylic acid) (PPy/γ-Fe2O3/P(MMA-MAA)) nanocomposite polymer particles were then prepared by the seeded copolymerization of MMA and MAA in the presence of magnetic PPy/γ-Fe2O3 nanocomposite seed particles. The structure and morphology of the prepared nanocomposites were confirmed by different instrumental techniques such as Fourier transform IR spectroscopy, UV−visible spectroscopy, electron micrographs, XRD and X-ray photoelectron spectroscopy. The electrical and magnetic properties were also investigated. The carboxyl functional electromagnetic PPy nanocomposite polymer particles should be useful for the immobilization of drugs or biomolecules to design electrically stimulated drug delivery systems for modulating the activities of nerve, cardiac, skeletal muscle and bone cells. © 2016 Society of Chemical Industry