Guatato-Lopez Toni Beth, Asuncion-Astronomo Alvie, Santos Gil Nonato C
Department of Physics, College of Science, De La Salle University, Philippines.
Department of Science and Technology - Central Office, Philippines.
Heliyon. 2024 Dec 20;11(1):e41394. doi: 10.1016/j.heliyon.2024.e41394. eCollection 2025 Jan 15.
Exposure to mid-energy radiation poses significant health risks, necessitating the development of effective shielding materials. Traditional lead-based shields, while effective, have significant drawbacks including toxicity and environmental concerns. This study investigates the potential of lead-free epoxy resin nanocomposites, incorporating bismuth oxide, nickel oxide, and cerium oxide, for mid-energy radiation protection. Nanocomposites were fabricated using an open mold casting technique, and their physical properties were characterized via scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyses. Further morphological analysis was conducted using a compound microscope and image processing software, ImageJ, to investigate the distribution of the particles on the polymer matrix. The radiation shielding effectiveness of the composites was evaluated using Na-22, Cs-137, and Mn-54 gamma sources in a gamma spectroscopy setup in Philippine Nuclear Research Institute. The results revealed that pure epoxy resin exhibited higher attenuation coefficients compared to the modified composites, primarily due to the challenges in achieving uniform dispersion of metal oxides within the polymer matrix. Agglomeration of nickel oxide nanoparticles was particularly noted, leading to reduced shielding performance. Average mass attenuation coefficients obtained in this experimental setup reached up to 0.08-0.1 cm/g for energy range 500-900 keV. Radiation protection efficiency (RPE) measurements indicated that pure epoxy resin achieved an RPE of approximately 6% across different sources, highlighting its potential for practical applications in medical imaging, industrial radiography, environmental monitoring, and nuclear power plants. This study underscores the importance of nanoparticle dispersion and provides insights into the development of lightweight, lead-free, and efficient radiation shielding materials. Future work should focus on optimizing synthesis methods to improve homogeneity and radiation protection efficacy of polymer-based composites.
暴露于中能辐射会带来重大健康风险，因此需要开发有效的屏蔽材料。传统的铅基屏蔽材料虽然有效，但存在包括毒性和环境问题在内的重大缺点。本研究调查了包含氧化铋、氧化镍和氧化铈的无铅环氧树脂纳米复合材料用于中能辐射防护的潜力。纳米复合材料采用开放式模具浇铸技术制备，其物理性能通过扫描电子显微镜（SEM）和能量色散X射线（EDX）分析进行表征。使用复合显微镜和图像处理软件ImageJ进行进一步的形态分析，以研究颗粒在聚合物基体上的分布。在菲律宾核研究所的伽马能谱装置中，使用Na-22、Cs-137和Mn-54伽马源评估了复合材料的辐射屏蔽效能。结果表明，与改性复合材料相比，纯环氧树脂表现出更高的衰减系数，这主要是由于在聚合物基体内实现金属氧化物均匀分散存在挑战。特别注意到氧化镍纳米颗粒的团聚，导致屏蔽性能降低。在该实验装置中获得的平均质量衰减系数在500-900 keV能量范围内达到0.08-0.1 cm/g。辐射防护效率（RPE）测量表明，纯环氧树脂在不同源上的RPE约为6%，突出了其在医学成像、工业射线照相、环境监测和核电站实际应用中的潜力。本研究强调了纳米颗粒分散的重要性，并为开发轻质、无铅和高效的辐射屏蔽材料提供了见解。未来的工作应专注于优化合成方法，以提高聚合物基复合材料的均匀性和辐射防护效能。
