Evaluation of the structural and optical characters of PVA/PVP blended films

The effect of gamma irradiation on the optical and structural properties of poly(vinylalcohol) (PVA)/poly (vinylpyrrolidone) (PVP) blends was investigated in this study. The PVA/PVP films were formulated by mixing and casting method with increasing PVA ratios. The dried films were irradiated at 30 kGy and the impact of gamma irradiation on the characteristics of these films was inspected using FTIR, XRD, SEM and UV vis techniques in the wavelength range (200-1200) nm. Swanepole method was used to compute the optical constants, optical band gap and complex dielectric constant whereas Wemple-DiDmenico model was applied to develop the optical dispersion parameters E-o and E-d. Additionally, the high frequency dielectric constant (epsilon(infinity)) for all films was recorded. A slight shift in the FT-IR spectra and increase in the transmittance for all films post-irradiation were detected and the XRD analysis depicted the crystalline nature of the PVA/PVP films which was further confirmed by the surface morphology images obtained by the SEM. In conclusion, gamma irradiation and increasing the PVA to PVP ratio improved the optical properties of the films.