Highly Transparent, Flexible, and Lead‐Free X‐Ray Shielding PVA/Sorbitol Composites With Tungstate Ions

ABSTRACT There is a growing demand for lead‐free, highly transparent, high‐performance X‐ray shielding materials that are both flexible and contain high concentrations of metals. This work demonstrates a flexible, transparent composite made from sodium polytungstate (SPT) incorporated into a matrix consisting of polyvinyl alcohol (PVA) and sorbitol at a concentration of 59 wt.%. The unique particle‐free fabrication of this material enables homogeneous distribution of the SPT without the need for surfactants, surface modifications, or ultrasonic processing. This composite exhibits 90% transmittance at 600 nm along with exceptional flexibility and a density of 2.56 g cm ⁻³ . Tungsten ions in the matrix undergo hydrogen bonding with ‐OH groups in the PVA and sorbitol. These bonds are confirmed by shifts in the ─OH stretching peak in infrared spectra. This composite provides an X‐ray shielding value of 0.14 mmPb at a thickness of 1.53 mm, significantly exceeding the value of 0.09 mmPb at a thickness of 1.70 mm for a lead‐containing commercial product. This performance surpasses that of state‐of‐the‐art transparent shielding materials, thus offering an unprecedented combination of softness, clarity, and radiation protection. The material developed in this work could have applications in the fields of medicine, nuclear energy, aerospace, and optoelectronics.