Comparative study of ferromagnetic behaviour in bare and PMMA modified manganese ferrite (MnFe 2 O 4 ) nanoparticles

Manganese ferrite (MnFe 2 O 4 ) nanoparticles have numerous applications in biomedical and applied fields. Surface modification of MnFe 2 O 4 with a variety of modifiers can to a large extent change the characteristics of manganese ferrite nanoparticles which includes magnetic, structural, optical, electrical and biomedical. In the present work, manganese ferrite was surface modified with polymethylmethacrylate (PMMA). The characterization of the as synthesized PMMA modified manganese ferrite nanoparticles was performed employing particle size analysis, transmission electron microscopy, energy dispersive X-ray analysis, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermal gravimetric analysis (TGA) and vibrating sample magnetometry technique. The particle size of the bare and PMMA modified MnFe 2 O 4 NPs were 66.13 nm and 11.12 nm respectively. Upon surface modification with PMMA, it was observed that the ferromagnetic manganese ferrite nanoparticles exhibited a drastic change in their magnetic character and behaviour that can be confirmed by observing the increased coercivity ( H c = 97.41 O e ) and magnetic moment ( µ B = 0.43). The TGA analysis of bare and PMMA modified MnFe 2 O 4 NPs revealed a total percentage weight loss of 2.35% and 21.02% respectively.