SBIR Phase II: Manufacturing Feasibility of New Radiation Shielding Fabrics

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project includes the reduction of lead and toxic elements used as radiation shielding in medical, dental, and veterinary settings. Lead and several of its salt composites have been the go-to radiation shielding material, but there have been documented instances of lead contamination to radiation workers. The proposed technology replaces lead and other elements used in radiation shielding with the safe and non-toxic element bismuth. This project focuses on the technical challenges related to molding new, lighter weight, cleanable, flexible, and elastic radiation shielding materials that can be used to produce garments that are much lighter and more ergonomic for medical personnel who wear radiation shielding for a large portion of their workday. This technology is built on new scientific understandings of bismuth surface stabilization chemistry and chemical engineering in very high-density microparticle composite materials. By tailoring the surface chemistry of bismuth particles, the material properties change dramatically on the macro property scale. In Phase I, the company demonstrated the feasibility of producing the final material, including the identification of polymers, scale-up of materials, and compounding that generated a fabric with exceptional elasticity, high X-ray attenuation, and a very thin profile for its target weight. While composite materials with greater than 85 % by weight bismuth particle filler requires specialized techniques and molding requirements, it yields a superior final material that outperforms all radiation shielding fabrics currently on the market. This project addresses a number of these processing challenges and fabrication techniques. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.