Effect of synthesis method on magnetic and thermal properties of polyvinylidene fluoride/Fe 3 O 4 nanocomposites

Polyvinylidene fluoride magnetic nanocomposite films were prepared by solution casting using two types of magnetic nanoparticles: (a) magnetic nanoparticles synthesized by co-precipitation method using oleic acid as a coating agent and (b) Fe 3 O 4 nanoparticles prepared by hydrolysis method without using a coating agent. Dynamic light scattering measurements showed mean diameters of 135 and 46 nm in co-precipitation and hydrolysis methods, respectively. Scanning electron microscopy showed that the magnetic nanoparticles were uniformly dispersed inside the polymer matrix. X-ray diffraction confirmed that Fe 3 O 4 nanoparticles induced nucleation of β- crystalline phase in the matrix polymer. The thermal properties of polyvinylidene fluoride magnetic nanocomposites were evaluated by differential scanning calorimetry. The decrease in crystallinity of the nanocomposites was concomitant with the increase in the melting temperature. The magnetic properties of the nanocomposites were investigated by vibrating sample magnetometer. The magnetic properties increased with increasing Fe 3 O 4 content and the polyvinylidene fluoride magnetic nanocomposites prepared by hydrolysis method showed higher magnetization.