Nickel oxide magnetic nanocomposites in an imine polymer matrix

Nanocomposites of nickel(II) oxide in a polyimine matrix have been synthesi zed by a very simple method. The nickel oxide nanoparticles were precipitat ed in situ within the polymer matrix by drying a polymer-metal complex unde r mild conditions, without the need for any basic or oxidizing treatment. T he polymer-metal complex results from suspending the polymer in a solution of the metal. The size distribution of the nickel oxide nanoparticles conta ined in the composite shows two different populations with average sizes 12 and 33 nm, respectively. Magnetic susceptibility measurements of the mater ials reveal the presence of two contributions to the magnetic system. The f irst has paramagnetic character and arises from the metal-organic matrix. T he second consists of frequency-dependent maxima that are typical of superp aramagnetic behavior and is related to the presence of nickel oxide nanopar ticles.