Effect of polyethylene glycol 4000 in magnetic properties of 0.2SiO₂0.5FeO0.3CaO glass ceramic

The synthesis of bioactive magnetic glass ceramics for hyperthermia treatment is still far from optimization due to the variable performance of many nanostructured systems. 0.2SiO₂0.5FeO0.3CaO glass ceramics were synthesized by sol–gel method at room temperature with a precursor to solvent ratio 1:5. The effect of adding polyethylene glycol 4000 (PEG4000) with 2, 4, 8, 12 and 16 wt% in the final stage of the sol preparation, on the magnetic and phase properties of the samples was studied. Heat treatment of the samples was done at 680 and 760°C. Phase analysis showed that maghemite and hematite phases have crystallized. By adding PEG4000 from 2 to 12 wt%, the saturation magnetization of the samples increased from 6.9 to 14.95 emu g^-1 . Further increase of PEG did not have much effect on improving the magnetic properties. It was also seen that heat treatment at higher temperatures led to a decrease in magnetic properties. (author)