Preparation and properties of novel, flexible, lead-free X-ray-shielding materials containing tungsten and bismuth(III) oxide

Novel, flexible, lead-free X-ray-shielding composites were prepared with a high-functional methyl vinyl silicone rubber (VMQ) matrix with W and Bi2O3 as filler materials. To verify the advanced properties of the lead-free material, composites with the same mass fraction of PbO were compared. With the X-ray energy ranging from 48 to 185 keV, the W/Bi2O3/VMQ composites exhibited higher X-ray-shielding properties. As the filler volume fraction decreased, the tensile strength, elongation, tear strength, and flexibility of the W/Bi2O3/VMQ composites increased. The Shore hardness of the W/Bi2O3/VMQ composites had a maximum value of 46.6 HA and was still very flexible. With decreasing filler volume fraction, the water-vapor transmission performances of the W/Bi2O3/VMQ composites increased, and the W/Bi2O3/VMQ composites also showed better water-vapor permeability. The heat-transfer properties of the W/Bi2O3/VMQ composites increased with increasing W content, and when the W content exceeded 70 wt %, the thermal conductivity of the W/Bi2O3/VMQ material was about 70.45% higher than that of the PbO/VMQ composite. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 43012.