Preparation and mechanical characterization of (rubber blend - micro lead) rubbery composites for shielding application

This present work, includes the preparation of rubber batches containing silicone rubber (SIR) (80pphr) and polyurethane (PU) (20pphr) with micro-lead powder in different loading, respectively (0,20.40,60,80,100,150,200,250,300pphr). The mechanical properties measured the device universal tensometer, such as tensile strength, elongation and modulus of elasticity, according standard specified of (ASTM D-412) were followed and the hardness property measured by (Hardness Shore A) was put through its steps according to the standard specification (ASTMD-1415). The results were selected, and the sample (10) consisting of (SIR 80/PU20 and micro-lead 300pphr) was chosen because it is more suitable for the required mechanical properties. The results observed that the ratios of micro-lead loading increased, the tensile and elongation decreased, and the hardness and elastic modulus increased. Rubber batches reinforced with micro-lead were exposed to an infrared (FTIR) test device with the addition of hexane, where there were no changes in the infrared spectrum of the rubber composites (SIR80/PU20/Micro-Pb). Sample No. (10) was shown that the scanning electron microscope (SEM) before and after adding hexane, where it was noted that the image (A) without hexane, the absence of homogeneity of lead. As for image (B) in the presence of hexane, we note the homogeneity of lead and the distribution of lead equally, so that radiation examination were measured the Geiger counter of two sources of radioactive elements were used, the caesium source Cs137 and the cobalt source Co60. The radiation is attenuated through the material, while the thickness of the half (X1/2) gradually contrasts according to the attenuation of the radiation. This work is applied in the applications of shields as a protective suit against harmful radiation.