Structural, optical, thermal, and dielectric properties of polyethylene oxide/carboxymethyl cellulose blend filled with barium titanate

Abstract

Nanocomposite films of polyethylene oxide/carboxymethyl cellulose (PEO/CMC)/barium titanate (BaTiO3) were prepared using the solution casting technique. The results of X-ray diffraction (XRD) analysis depicted the semicrystalline nature of PEO/CMC, which was largely reduced due to BaTiO3 loading. Fourier transform infrared (FT-IR) spectroscopy showed the interaction between the components of blend, PEO and CMC, through the formation of hydrogen bond and confirmed the interaction between BaTiO3 and the functional groups of PEO/CMC, in particular C-O-C for PEO and COO− for CMC. From the Ultraviolet/visible (UV/vis.) absorption spectra, the sharp absorption edge in the UV range for the filled samples was red shifted and the optical energy gap was also calculated. The effect of BaTiO3 on the glass transition, melting point, and decomposition temperatures of the prepared samples was investigated using differential scanning calorimetry (DSC) technique. From the AC conductivity results, the electrical properties were improved depending on temperatures, frequencies, and the BaTiO3 content within the polymeric matrix. This indicated the presence of charge carriers that transported within defect sites by hopping. Furthermore, the mechanism for AC conduction and its dielectric parameters had been studied. Transmission electron micrographs revealed the cubic shape for BaTiO3 with an average size range of 15–50 nm. These observations indicate that these nanocomposite samples are potential candidates in various industrial applications, such as pyroelectric sensors and electromechanical transducers, and in ceramic capacitors as a dielectric material inserted between the two electrodes.