Experimental evaluation of gamma radiation shielding characteristics of Polyvinyl Alcohol/Tungsten oxide composite: A comparison study of micro and nano sizes of the fillers

In this experimental work, Polyvinyl Alcohol-Tungsten oxide micro-and nanocomposites were fabricated in various weight percentages of 0, 10, 20, 30, and 40 wt%, through the solution method. The dispersion state of the inclusions into the polymeric matrix was studied through the SEM analyzes. Then, the linear attenuation coefficient, mass attenuation coefficient, half-value layer, tenth-value layer, and mean free path of the samples were measured using a Geiger counter for different gamma-rays of Co-57, Tl-201, Ga-67, (99)mTc, Ba-133, and Cs-137 radioactive sources. It was shown that increasing the concentration of the WO3 fillers in the PVA matrix increased the attenuation coefficients of the composites significantly. Besides, the attenuation coefficients of the nanocomposites were significantly larger than those of the microcomposites due to high surface-to-volume ratio of the tungsten oxide nano-particles compared to the microcomposites.& nbsp;