γ-irradiation induced effects on structural, morphological and photoluminescence properties of PEO-PVA blended polymer films

Abstract

PEO/PVA blends have been prepared to investigate the effect of gamma rays on the structural, morphological and photoluminescence properties. The studies of non-irradiated and irradiated samples with radiation doses of 10 kGy were examined by using XRD, ATR-FTIR, Optical microscopy and PL. Gamma photons induced important chemical rearrangements, especially by PVA hydroxyl groups. We found that the crystallinity rate is strongly influenced by radiation. In this context, one could predict that the immiscibility of PVA with PEO and the interactions between the chains are of the electrostatic type. A structural-scale disturbance due to the radical formation leads to spherulitic texture modifications of the PEO. Due to the luminescence properties, the blend samples behave like core-shell nanoparticles. This phenomenon is due to the fact that the PVA polymer played the role of shell. Irradiation makes it possible to obtain well-ordered spherulites and to get a high pore density. The irradiated blend showed a higher quantum yield. The significant chemical and morphological changes caused by gamma radiation favored the optical recombination of hydroxyl groups.