Development of New Lead-Free Composite Materials as Potential Radiation Shields

Abstract

Utilizing a polymer-based radiation shield offers lightweight, low cost, non-toxic compared to lead and solution for eliminating generated secondary neutrons. Incorporating silicon (i.e., one of the most abundant elements) in new applications, such as shielding, would have an impact on the economy and industry. In this study, seven potential shielding materials, composed of silicon, silicon carbide, and boron carbide embedded ethylene vinyl acetate (EVA) copolymers, are proposed. The shielding performance of these composite materials, including the attenuation coefficients (µ), the mass attenuation coefficients (µm), the half value layer (HVL), the mean free path (MFP), and the radiation protection efficiency (RPE) were examined using photon beams. Measured µm were verified against the calculated values. The averaged agreement was within ±7.4% between the experimental measurements and the theoretical calculation results. The HVL and MFP measured values for the polymer composites were lower than that for the pure EVA polymer, indicating the fillers in the polymers enhanced the shielding performance. The EVA + SiC (30%) and EVA + Si (15%) + B4C (15%) composites required the lowest thickness to stop 50% of the incident photons. The evaluation of experimental results of the RPE revealed that the polymer composites containing SiC (30%), Si (15%) + B4C (15%), or SiC (15%) + B4C (15%) succeeded in blocking 90–91% of X-rays at nearly 80 keV. However, a thicker shield of the proposed composite materials or combined layers with other high-Z materials could be used for higher energies.

The Characterization of Silicone-Tungsten-Based Composites as Flexible Gamma-Ray Shields

“…As reported by Mansour Almurayshid et al, the linear attenuation of the composites containing ethylene vinyl acetate (EVA) polymer and Si or SiC or B 4 C at the gamma-ray energy of 0.662 MeV is around 0.9 cm −1 [31]. The linear attenuation of the siliconetungsten based composites here is higher than that of EVA-Si based composites, which may ascribe to the high concentration of tungsten used in our composites.…”

Research Progress with Membrane Shielding Materials for Electromagnetic/Radiation Contamination

“…However, with the rapid pace of technological development, the above-mentioned membrane shielding materials can no longer meet the problem of electromagnetic/radiation pollution caused by many types of modern technological devices. Therefore, more researchers have devoted themselves to the exploration of membrane shielding materials to protect humans and their environment, and these efforts have expanded to the preparation of many new membrane-based shielding materials, such as the use of 3D printing design [ 35 , 36 , 37 , 38 ], as well as the development of MXene-based [ 39 , 40 , 41 , 42 ], carbon-based [ 43 , 44 , 45 , 46 ], iron-based [ 47 , 48 , 49 , 50 ], cellulose-based [ 51 , 52 , 53 , 54 ], and lead-free materials [ 55 , 56 , 57 , 58 , 59 , 60 ]. The traditional electromagnetic/radiation shielding method was to directly blend conductive fillers to improve the shielding performance [ 61 ], especially in the field of electromagnetic radiation shielding.…”

Radiation Shielding Tests of Crosslinked Polystyrene-b-Polyethyleneglycol Block Copolymers Blended with Nanostructured Selenium Dioxide and Boron Nitride Particles

“…More et al’s review research focused on the synthesis and efficacy of polymeric-based substances blended with nano-additives for radiation safeguarding [ 25 ]; furthermore, they introduced the recycling of polymer structures. Almurayshid et al suggested that polymer-based shielding materials (e.g., ethylene vinyl acetate (EVA) polymers, Si, SiC, B 4 C) offer a mild, low-cost, nontoxic means of annihilating the harmful effects of generated neutrons, and the conclusions of their research illustrated that the blended materials (i.e., Si, SiC, B 4 C) in the polymer enhanced the attenuation ability in low-energy regions [ 26 ]. Muthamma et al aimed to investigate the gamma shielding properties of diglycidyl ether of bisphenol A (DGEBA) epoxy-resin-based micro- and nano-Bi 2 O 3 composites, and they found that nanocomposites have preferable gamma attenuation at all energy regions (from 0.356 to 1.332 MeV), compared to microcomposites with identical doping; furthermore, this work elicited the importance of nanostructural additives to improve the routine activities of the composites [ 27 ].…”