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Pure and Mn2+ doped poly(vinyl chloride) (PVC) polymer films were prepared using the solution cast technique. The prepared samples have been characterized by X-ray diffraction (XRD), UV-Vis Spectroscopy (UV-Vis), Fourier transform infrared (FTIR) Spectroscopy, Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Electron Paramagnetic Resonance (EPR) and Scanning Electron Microscopy (SEM) studies. TGA/DSC analysis reveals that the sample is thermally stable upto 350 0C. The morphology of the polymer films was studied by SEM. The optical absorbance of the polymer films was measured in the 200-900 nm wavelength range. The absorption edge, direct band gap and indirect band gap have been evaluated. The FTIR spectrum exhibits several bands characteristics of stretching and bending vibrations of C -Cl, C -H, C = C and O -H groups. The EPR Spectra at room temperature were used to calculate the number of spins and paramagnetic susceptibility as a function of dopant concentration. All the Mn 2+ doped PVC samples exhibit a signal centred at g eff = 1.9. The observed variation in the EPR signal intensity is due to the variation in the dopant concentration. The complexation of Mn 2+ ion with the polymer was confirmed by XRD studies.

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Pure and VO2+ doped methacrylic acid ethylacrylate (MAA:EA) copolymer films were prepared by using a solution casting method. Various techniques including X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, scanning electron microscopy and electron paramagnetic resonance were employed for characterization of the samples. XRD patterns showed some degree of crystallinity of the doped polymer films due to interaction of the MAA:EA copolymer with VO2+. FT-IR spectral studies of pure and VO2+ doped MAA:EA copolymer films displayed significant structural changes within the doped copolymer film indicating the complexation. The optical absorbance of the pure and VO2+ doped films were measured in the 200 nm to 800 nm wavelength range. The values of the absorption edge and indirect band gaps were calculated. The optical band gap decreased with the increase of mol% of VO2+. From the EPR spectra, the spin- Hamiltonian parameters (g and A) were evaluated. The values of the spin-Hamiltonian parameters confirmed that the vanadyl ions were present in MAA:EA copolymer films as VO2+ molecular ions in an octahedral site with a tetragonal compression (C4v). The morphology of the copolymer samples was examined by scanning electron microscopy. The enhanced crystalline nature of the doped copolymer was identified from SEM analysis.

Pure and Mn