Optical and dielectric properties of poly(vinylacetate)/lead oxide composites

Abstract

Composite films of poly(vinylacetate)/red lead oxide have been prepared by mixing the fine lead oxide particles into polyvinylacetate solution under ultrasonication followed by film casting technique. Structural, optical and dielectric properties have been performed to characterize these composites films and compared their properties to pure PVAc film. The changes in the structural of the prepared films were investigated by X-ray diffraction (XRD) and FT-IR spectra. It has been observed that the crystallinity of the composites films depends on the Pbcontent. Optical spectra of the composites films showed direct allowed band gaps lying in the range of 5.0-4.6 eV which is lower than that of PVAc. Frequency and doping level dependence of dielectric constant (e 0 ), ac conductivity (r ac ) and tangent loss (tand) have been measured. The values of e 0 were decreased with increasing in frequency, which indicates that the major contribution to the polarization comes from orientation polarization. The ac conductivity is more for doped PVAc than that of undoped PVAc. The experimental results show that e 0 and r ac increase with adding of lead oxide in PVAc. The controllable of optical and dielectric properties of the composite film will draw much attention for potential applications.

Preparation of Chloro Penta Amine Cobalt(III) Chloride and Study of Its Influence on the Structural and Some Optical Properties of Polyvinyl Acetate

“…The behavior of PVAc/[Co(NH 3 ) 5 Cl]Cl 2 composite agrees with PVAc/Pb 3 O 4[18] and PVAc/TiO 2[19]. With 9 wt.% concentration the peaks belong to [Co(NH 3 ) 5 Cl]Cl 2 observed with lower intensity because [Co(NH 3 ) 5 Cl]Cl 2 structure is being capped with PVAc after formation of composites, which agrees with (Roy et al 2013)[20].…”

“…The absorption at any wavelength depends on the number of particles along the bath of the incident light (i.e., it depends on concentration of [Co(NH 3 ) 5 Cl]Cl 2 ) and on the length of the optical path passing through [32]. These results have a good agreement with Abdelaziz [18]. Absorption coefficient ( ) is defined as the ability of a material to absorb the light of a given wavelength.…”

“…This band is attributed to the carbonyl group[28]. It is observed that the wavelength corresponding to the absorption band like shoulder increases with increasing in [Co(NH 3 ) 5 Cl]Cl 2 content; this increase has been attributed to the minor structural inhomogeneities present in PVAc[18] which are due to growth of [Co(NH 3 ) 5 Cl]Cl 2 inside the polymeric matrix. As the composite films show a red shift behavior, these shifts indicate the complexation between the [Co(NH 3 ) 5 Cl]Cl 2 and the PVAc and may also be due to change in crystallinity with presence of additive[29].…”