10. Effect of Bi₂O₃ Particle Sizes and Addition of Starch into Bi₂O₃–PVA Composites for X-Ray Shielding

The effect of Bi₂O₃ particle sizes filled PVA composites on X-ray transmission for X-ray shielding purpose had been successfully fabricated and analyzed by using X-ray fluorescent spectroscopy (XRF) and mammography units with various low X-ray energy ranges. Besides, a preliminary investigation was carried out by using XRF unit to obtain the effect of starch addition into the composite on the X-ray transmissions by both particle sizes of Bi₂O₃–PVA composites. The results showed that the ability of the composite to attenuate the initial X-ray beam was augmented with the increased Bi₂O₃ weight percentage (wt%). The density of both particle sizes of Bi₂O₃–PVA composites was compared with the addition of 1 and 3 wt% starch, while a fluctuation of density occurred for the composites without starch. Moreover, the nanosized Bi₂O₃–PVA composite without starch did not exemplify better X-ray attenuation capability compared to its micro-sized counterpart even though their density was higher than the micro-sized Bi₂O₃–PVA composite. However, the nano-sized Bi₂O₃–PVA composite with starch offered better particle size effect for X-ray shielding ability than its micro-sized counterpart compared to the Bi₂O₃–PVA composites without starch.