  Iron oxide nanoparticles were prepared by sol -gel process. Insitu
polymerization of pyrrole monomer in the presence of oxygen in iron oxide
ethanol suspension resulted in a iron oxide - polypyrrole nanocomposite. The
structure and magnetic properties were investigated for varying pyrrole
concentrations. The presence of the gamma - iron oxide phase and polypyrrole
were confirmed by XRD and FTIR respectively. Agglomeration was found to be
comparatively much reduced for the coated samples, as shown by TEM. AC
susceptibility measurements confirmed the superparamagnetic behaviour.
Numerical simulations performed for an interacting model system are performed
to estimate the anisotropy and compare favourably with experimental results.
