Preparation And Settling Behavior Of Conductive Polymeric Nanoparticles

The small size of nanoparticles, which is responsible for the different properties of nanoparticles and nanostructured materials with respect to the bulk material such as electronic, optical, magnetic, chemical and mechanical et al., makes them suitable for new promising applications. Conducting polymer nanocomposites with both electrical and ferromagnetic properties have generated tremendous attraction, and they have become one of the most active research areas. Multi-component conducting polymer systems with nanoparticles of metal oxides can be tailored to exhibit, besides novel electrical, magnetic and optical propertied, also good film forming and processing properties. These materials are largely being used in nonlinear optics, electrochemical display devices, molecular electronics, electrical and magnetic shields and microwave absorbing materials. The large surface to volume ratio of the nanoparticles results in the formation of composites with unusual physical and chemical properties, which are quite different from the composite due to interaction at the molecular level.A facile method to prepare conducting polymer/Fe3O4 magnetic nanoparticles was developed. Fe3O4 nanoparticles were prepared first by chemical co-precipitation. Then polypyrrole (PPy)/Fe3O4 magnetic nanocomposite was prepared by in-situ polymerization in the presence of Fe3O4 nanoparticles. The mole ratio of PPy to Fe3O4, adding sequence of pyrrole monomer and oxidant, temperature et al., were taken into consideration as factors affecting the morphology of PPy/Fe3O4 magnetic nanocomposite and the optimum polymerization conditions were obtained. Due to its special electrical properties, conducting polymer has generated tremendous attraction in membrane science area as a membrane material or as an electromembrane component synthesized with other substrate membrane material. Combining the conductibility of conductive polymers with the good mechanical properties and permeability of substrate material, this kind of electromembrane possesses good electrochemical and mechanical properties. However, because of the conglobation character of nanoparticles and the polarity difference between nanoparticles and substrate material, the nanoparticles can't disperse homogeneously in substrate membrane material. So it's necessary to improve the dispersibility and stability of nanoparticle. Effects of electrolyte, polymer and magnetic field on the settling behavior of magnetic nanoparticles were studied.