Abstract
The effect of electron beam (EB) irradiation at different doses on the magnetic, microstructure, morphological and thermal properties of NiFe2O4/Thermoplastic Natural Rubber (TPNR) nanocomposite was investigated. The NiFe2O4/TPNR nanocomposite samples were prepared by using a Haake mixer in weight ratio of 12:88. The TPNR matrix consists of natural rubber (NR), liquid natural rubber (LNR) and high density polyethylene (HDPE) in weight ratio of 20:10:70. The samples were irradiated using a 2 MeV EB machine in doses from 0 - 200 kGy. Magnetic properties studied by using the vibrating sample magnetometer (VSM) at room temperature showed that the values of saturation magnetization (M-s), remanence magnetization (M-R) and the coercivity (H-C value increased with increasing doses of irradiation. The increase in M-s and M-R values is attributed to the increase in concentration of Fe3+ ions at octahedral B-site and decrease of concentration at the tetrahedral A-site in the NiFe2O4 cubic structure. X-ray diffraction (XRD) analysis of the samples showed that peak intensities decreased and the width of the peaks increased with increasing doses of irradiation. Scanning electron microscope (SEM) image of the nanocomposite cross section showed the presence of defects which is more visible with increasing doses of irradiation. In the case of thermal properties, differential scanning calorimetry (DSC) analysis showed that the crystallization temperature (T-c) and the degree of crystallinity (X-c) of the nanocomposite samples decreased with increasing doses of irradiation due to crosslinking of polymeric chains which hinders the growth of crystals.