Electrical and thermal behavior of PS/ferrite composite.

This work aims to study the effect of gamma radiation on the structure, thermal and electrical properties of PS/ferrite composite. The Ni0.6Cd0.4Fe2-xSmxO4 was prepared using a conventional sintering ceramic process. Ferrite powder and Styrene was mixed and achieve polymerization process by gamma irradiation at 50 kGy. The composite samples have single spinel phase structure. Stability of the crystalline structure and no phase transition due to irradiation are found. The bulk density decreases whereas X-ray density increases with increasing Sm contents for both ferrite and PS/ferrite. The tetrahedral radii rA remains constant with Sm content but octahedral radii rB increases for both ferrite and PS/ferrite composite. The grain size shows increasing trend for PS/ferrite composite. The PS nearly coat the grains and so their boundaries become faint and not sharp. The gamma radiation transfer Fe3+ to Fe2+ due to its ionizing effect. The Fe2+ occupy octahedral site and the stretching vibration of its bond with oxygen (Fe2+-O2-) gives absorption at about 392 cm-1, near octahedral absorption at 462 cm-1. The PS/Ni0.6Cd0.4SmxFe2-xO4 composite becomes thermally more stable than pure polystyrene. The activation energy of conduction Eσ has a small values and in the range of hopping conduction mechanism. [ABSTRACT FROM AUTHOR]