X-Ray and γ-Ray Shielding Efficiency of Polymer Composites: Choice of Fillers, Effect of Loading and Filler Size, Photon Energy and Multifunctionality

Use of X-rays and γ-rays have become inevitable in medical sectors like radiology, interventional cardiology and diagnostic imaging, radiation physics laboratories, nuclear reactors and accelerator facilities. As radiation exposures above permitted levels pose potential risk to personnel working in close proximity to these facilities, protective measures aimed at reducing the exposure for safeguarding against harmful effects of ionizing radiations are essential. Traditionally, lead and lead based materials have been used as efficient radiation shielding materials owing to the high atomic number and high density of lead. Presently, use of lead is discouraged due to its heavy weight, toxicity and long-term effects on the environment. Consequently, the last two decades have seen research on light weight and cost-effective polymer composites with appropriate additives, having good workability, high specific strength, thermo-chemical stability and radiation shielding efficacy, gaining momentum. This article gives an overview of the state-of-the-art polymer composites reinforced with different fillers studied for their use as effective radiation shields. Here, we summarize the recent advancement and current trends in polymer composites-based radiation shields highlighting the different approaches adopted, choice of polymer/fillers, shielding effectiveness in terms of either linear and/or mass attenuation coefficients, for those who venture into radiation research and development.