Electron beam-modified PVA/PVP films with tunable optical and surface properties for flexible electronics

Electron beam (EB) irradiation was applied to poly(vinyl alcohol)/poly(vinyl pyrrolidone) (PVA/PVP) blend films at doses ranging from 0 to 60 kGy to tailor their structural and functional properties. Mechanical, structural, surface, and optical characteristics were evaluated using tensile testing, UV–Vis spectroscopy, contact angle measurements, Fourier transform infrared spectroscopy, X-ray diffraction, and atomic force microscopy. An irradiation dose of 30 kGy produced the most pronounced property enhancements, resulting in a 43.5% increase in tensile strength and a 270% increase in elongation at break relative to the non-irradiated film. Improved crystallinity and surface energy were observed, accompanied by a reduction in water contact angle from 84.4° to 78.3°. Optical analysis revealed a decrease in the indirect and direct band gaps to 2.94 eV and 3.34 eV, respectively, along with a maximum Urbach energy of 7.08 eV. These findings demonstrate that controlled EB irradiation provides an effective route for tuning the performance of PVA/PVP blend films.