Thermal, Magnetic and Electrical Properties of PMMA Nanocomposites with Manganese and Zinc Ferrite Nanoparticles and Their Functionalization

Abstract

Manganese (MnFe 2 O 4 ) and zinc (ZnFe 2 O 4 ) ferrite nanoparticles were synthesized by the combustion method. Furthermore, the modification of these particles with a silane compound was performed. Thus, the particles produced were analyzed for morphology using Scanning electron microscopy (SEM), thermal stability, and composition assisted by Thermogravimetric analysis (TGA). It is noteworthy that the present work used an unprecedented Far-Fourier-transform infrared spectroscopy (Far-FTIR) technique to differentiate the types of ferrites and their surface functionalization, as it is a simpler, more efficient, and high-resolution method. It is worth mentioning that there are few comparative studies of zinc and manganese ferrites in the literature, much less distinguishing these ferrites simply and efficiently. In addition, there is also a lack of scientific knowledge about its chemical functionalization as compatibilization, especially silanization. Novel PMMA nanocomposites were prepared with the different synthesized particles in the contents from 0.1 % to 1.0 wt.% by the in situ polymerization technique. The nanocomposites were characterized by the analysis of SEM, TGA, Differential scanning calorimetry (DSC), and FTIR mainly by their morphology, thermal resistance, glass transition temperature, proving the chemical interactions, electrical conductivity, capacitance, and dielectric constant. Furthermore, it was evidenced that, in addition to the improvements in thermal, electrical, and interface properties, the produced nanocomposites showed excellent electromagnetic shielding properties even at low filler contents. It is noteworthy that the capacitance increases 63 % for the composite with 1.0 % zinc ferrite and 43 % for manganese ferrite. Also, the electromagnetic absorption results proved that even the low filler contents tested in this work, up to 1.0 %, presented an excellent potential for applying as electromagnetic shielding materials, reaching up to 70 % attenuation with the use of zinc ferrite. Both ferrites showed excellent results, even superior to those found in the literature for other particles with the same purposes, and still needed a lower content to achieve excellent results.