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Abstract The physical and chemical structural changes occurred due to the electron beam irradiation of PVA/V2O5 and PVA/PVP/V2O5 composites were investigated. A series of poly (vinyl alcohol)/poly (vinyl pyrrolidone)/vanadium pentaoxide xerogel composites were prepared in different ratios and exposed to different electron beam irradiation doses. Changes in the physico-chemical properties of composites with increasing irradiation dose were investigated using Fourier transformer infrared spectroscopy (FTIR), UV/VIS spectrophotometer, Xray diffraction (XRD), and thermal gravimetric analysis (TGA). The analysis using FTIR, UV/VIS, X-ray, XRD, FTIR spectroscopy reveal that the characteristic stretching frequencies for the prepared PVA/V2O5 and PVA/PVP/V2O5 composites are shifted towards lower frequencies side, as compared to PVA and PVA/PVP composites. Also, the FTIR investigation suggests that the inorganic and organic components strongly interact during processing and irradiation manifested that (PVA/PVP) blends were misible blends. XRD data illustrate that PVA/V2O5 and PVA/PVP/V2O5 have many aggregated pores which have been reduced due to the homogenous distribution of V2O5 in polymer matrix. Also, the diffraction Abstract II patterns of PVA/V2O5 and PVA/PVP/V2O5 composites show broad and lower peaks as compared with PVA and PVA/PVP matrixes suggesting a decrease in the crystallinity of V2O5 loaded matrices. Therefore, XRD indicates that the polymer matrix PVA and /or PVA/PVP are intercalated within the interlayer region of the V2O5. UV/VIS investigation indicated that either irradiation or loading the polymer matrix with various content of V2O5 affect the absorption bands and optical properties of the hybrid composite compared with pure PVA and PVA/PVP composite. TGA study indicates that the thermal stability of PVA/V2O5 and PVA/PVP/V2O5 composites was enhanced as compared with unhybridized ones as a result of either irradiation or V2O5 loading. The crystalinity degree of the matrix changed due to the blending, xerogel addition and/or irradiation process. |