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Chloro penta amine cobalt(III) cloride [Co(NH3)5Cl]Cl2was prepared and then characterized by Fourier transform infrared spectroscopy and X-ray diffraction. The obtained results indicated the formation of orthorhombic [Co(NH3)5Cl]Cl2nanoparticles of ≈28.75 nm size. Polymeric films based on polyvinyl acetate (PVAc) doped with chloro penta amine cobalt(III) cloride [Co(NH3)5Cl]Cl2in different weight percent ratios were prepared using the solvent cast technique. The complexation of the additive with the polymer was confirmed by FTIR and SEM studies. The XRD pattern revealed that the amorphousicity of PVAc polymer matrix increased with raising the [Co(NH3)5Cl]Cl2content. Parameters such as extinction coefficient, refractive index, real and imaginary parts, and optical conductivity were studied by using the absorbance and measurements from computerized UV-visible spectrophotometer in the spectral range 190–800 nm. This study showed that the optical properties of PVAc were affected by the doping of [Co(NH3)5Cl]Cl2where the absorption increased by leveling up [Co(NH3)5Cl]Cl2concentration. The nature of electronic transition from valence band to conduction band was determined and the energy band gaps of the composite films samples were estimated by UV-visible spectrum. It was observed that the optical conductivity increased with photon energy and with the increase of [Co(NH3)5Cl]Cl2concentration.

Films of PVA/PVP/MnO2 nanostructures were fabricated for pressure sensors fields with lightweight, flexible and low cost compare with other sensors. The structure, dielectric and optical characteristics of PVA/PVP/MnO2 nanostructures have been studied. The results showed that the dielectric constant, dielectric loss and A.C electrical conductivity of PVA/PVP blend are enhanced with the increase in MnO2  NPs content. The dielectric constant and  dielectric loss decrease while the A.C electrical conductivity increases with the increase in frequency. The optical characteristics of PVA/PVP/MnO2 nanostructures showed that the absorbance was rise with increasing of the MnO2  NPs content. The indirect energy gap of PVA/PVP blend was reduced with increase in MnO2  NPs content. The optical constants of blend are changed with  the increase in MnO2  NPs content. The pressure sensor application results of PVA/PVP/MnO2 nanostructures showed that the electrical capacitance  (Cp) increases with the rise in applied pressure.