Abstract
Summary: Ultrasonic irradiation was employed to prepare polypyrrole (PPY)/Fe~3~O~4~ magnetic nanocomposite by chemical oxidative polymerization of pyrrole in the presence of Fe~3~O~4~ nanoparticles. This approach can solve the problem in the dispersion and stabilization of inorganic nanoparticles in polymer. The structure and properties of PPY/Fe~3~O~4~ nanocomposite were characterized by TEM, XPS, FTโIR, TG, and XRD. PPY deposits on the surface of Fe~3~O~4~ nanoparticles while Fe~3~O~4~ nanoparticles are dispersed at the nanoscale by ultrasonic irradiation, which leads to the formation of polypyrroleโencapsulated Fe~3~O~4~ composite particles. The doping level of PPY in PPY/Fe~3~O~4~ nanocomposite is higher than that of neat PPY. The composites possess good electrical and magnetic properties. With the increase in the Fe~3~O~4~ content, the magnetization increases and the conductivity first increases and then decreases. When the Fe~3~O~4~ content is 40 wt.โ%, the conductivity reaches a maximum value of 11.26 Sโยทโcm^โ1^, about nine times higher than that of neat PPY, and the saturation magnetization is 23 emuโยทโg^โ1^. Also, the introduction of Fe~3~O~4~ nanoparticles enhances the thermal stability of PPY/Fe~3~O~4~ composite.
Conductivity of PPY/Fe~3~O~4~ composite at different Fe~3~O~4~ content.
magnified imageConductivity of PPY/Fe~3~O~4~ composite at different Fe~3~O~4~ content.