Study of Lead Nitrate Doped PVA/PVP Blend Films using EDXRF and Complementary Techniques

摘要

Polyvinyl alcohol (PVA) - polyvinyl pyrrolidone (PVP) blend solutions were doped with different amounts of lead nitrate (Pb(NO3)2), in the doping range varying from 2.7 wt% up to 50.5 wt%. In this paper, the study of these films using Energy Dispersive X-ray Fluorescence (EDXRF) technique in 2 π geometrical configuration is explained. In order to study K shell (K_(αβ)) X-rays from the prepared films, cobalt-57 radio-isotope and thallium doped sodium iodide [NaI(Tl)] scintillation gamma/ x-ray detector system with 1k MCA are used. The experiment was complemented by Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray Spectroscopy (EDS). The SEM images revealed that the filler (Pb(NO3)2) causes significant micro-structural changes in doped PVA/PVP blend films, revealing phase separation of the material into a polymer rich region and a dopant rich region at doping levels beyond 12.1 wt%. In addition to SEM, the EDXRF study is complemented by X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) scans on the Pb (NO3)2 doped PVA/PVP blend films.