Enhancement of the magnetic and dielectric properties of cobalt nanoferrite/polymethyl methacrylate composites

Abstract

Different concentrations of Co-nanoferrite/ polymethyl methacrylate (PMMA) composites were prepared. The effect of Co-nanoferrite concentration (x) on the structure, magnetic and dielectric properties of PMMA has been studied. X-ray and TEM measurements revealed the single phase of Co-ferrite of crystallite size 11 nm. FTIR spectra showed the characteristic peaks of PMMA and a shift in the main peak at high Co-nanoferrite concentrations which was explained in terms of its particle size. Magnetic hysteresis curves show the increase of magnetization of the composite with increasing concentration. It was found that both the dielectric constant (e 0 ) and loss (e 00 ) decrease rapidly with increasing frequency in the low frequency range and beyond that remain constant. This result was discussed in terms of the response of the different types of polarization to the frequency of the electric field. Moreover, both e 0 and e 00 increased for ferrite concentration 0 B x B 0.8 and then decreased for higher x values. This was explained according to the increased amount of the dispersed ferrite particles within the polymer matrix and the continuous increase in the particles agglomerations of the nanoferrite with increasing concentration.

Novel Polyimide/Copper-Nickel Ferrite Composites with Tunable Magnetic and Dielectric Properties

“…As can be seen from Figure 4a and Table 3, increasing ferrite insertion ratio led to the progressive modification of M s and M r , while coercivity stayed in the same range (79-90 Oe). M s and M r increased in a linear fashion for 10-30% filler concentration, as was expected, since an increase in particle concentration leads to an increase in the magnetic moment per unit volume of the sample, and hence its magnetization increases [4]. Between insertion ratio of 30% and 40%, M s and M r exhibited a lower increase, indicating a tendency of the composites to reach magnetic saturation by canceling the magnetic moments due to interparticle interactions.…”

“…Novel magnetic polyimide/copper-nickel ferrite composites were developed using cerium-doped ferrite particles, namely, NiFe 4 , as inorganic fillers. An aromatic polyimide containing pendant carboxylic groups was used as polymer matrix in order to ensure a good dispersion of the filler particles.…”

“…In this regard, the polymeric phase confers flexibility and good processability, while the inorganic phase gives them thermal, optical, electrical, or magnetic characteristics [ 1 ]. Magnetic polymer nanocomposites are a particularly well-studied subgroup, since they can easily be prepared by incorporating magnetic inorganic nanoparticles into a polymer matrix, and have been extensively explored in a wide variety of high-performance applications, including in vivo imaging, photocatalysis, and heavy metal absorption [ 2 , 3 , 4 , 5 ].…”

Exploration of the role of nanoferrite load and particle size on the rheometric, mechanical, and dielectric properties of (Co0.2Zn0.8Fe2O4/NBR) nanocomposites

“…They are accumulated at the phase boundaries which leads to increase the interfacial polarization. [24] Moreover, the hopping increases at low frequencies but begins to decrease as the frequency tends to high values as it fails to follow the changes in the direction of the external field. Accordingly, ρ ac , ε 0 , and ε 00 have high values at low frequency and their values decrease by increasing frequency.…”