Synthesis, thermal and dielectric investigations of PVDF/PVP/Co0.6Zn0.4Fe2O4 polymer nanocomposite films

This study aims to prepare and examine the structure, thermal and dielectric
properties of Polyvinylidene fluoride (PVDF)/Polyvinylpyrrolidone (PVP)/
Co0.6Zn0.4Fe2O4 nanocomposite films. The data were collected via X-ray
diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform
infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and dielectric
measurements. The XRD spectrum of the Co0.6Zn0.4Fe2O4 ferrite sample showed
a spinel crystal structure with an average size 15 nm. In the X-ray diffraction
spectra of the PVDF-Co0.6Zn0.4Fe2O4 polymer nanocomposites, b-phase
diffraction peak appeared at 2h = 0.2. SEM images of all the nanocomposite
films exhibited a homogeneous distribution of nanostructured Co0.6Zn0.4Fe2O4.
FTIR spectra depicted the absorption bands for a, b and c-phase of PVDF as well
as the carbonyl group of PVP. From TGA analysis, the activation energy for
thermal decomposition decreased from 285.73 to 248.97 kJ/mol.K. Besides, there
is a decrease in both DH and DG values with an increase in the Co0.6Zn0.4Fe2O4
concentration. The static dielectric constant (es), the high-frequency dielectric
constant (e?) and the dielectric strength (De) for these nanocomposites were
lower than the pure PVDF/PVP film. The DC conductivity values were 2.27 9
10-14, 1.63 9 10-8, 2.04 9 10-10 and 1.61 9 10-8 S/cm for 0.0, 1.0, 3.0 and 5.0
wt% of Co0.6Zn0.4Fe2O4.