Tungsten oxide nanoparticles were synthesized. Metal/polymer composites of nano-sized WO and poly vinyl alcohol were blended by the casting method with concentrations of WO. The structural, morphological, thermal, and mechanical characteristics of the prepared samples were investigated. The γ-ray attenuation properties of the synthesized composites were examined using γ-ray spectrometers, and the γ-ray mass absorption coefficients were measured using 662 keV γ-ray of Cs radioactive source. The defects and microstructure changes of the composites were probed using positron annihilation lifetime and Doppler broadening techniques. The shielding performance and thermal stability improved with increasing the concentration of WO, and some of the mechanical properties, in particular the elongation at break, deteriorate. The contribution of WO has a strong effect on reducing the relative fractional free volume, which in turn helps to increase the γ-ray absorption of the composites. The use of a 50–70 % WO/PVA composite is recommended.

中文翻译：

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纳米氧化钨/聚乙烯醇复合材料的结构、形貌、热学、力学、正电子湮灭和γ射线屏蔽研究

合成了氧化钨纳米粒子。通过铸造法将纳米级 WO 和聚乙烯醇的金属/聚合物复合材料与一定浓度的 WO 共混。研究了所制备样品的结构、形态、热和机械特性。利用γ射线能谱仪检测了合成复合材料的γ射线衰减性能，并利用Cs放射源的662 keV γ射线测量了γ射线质量吸收系数。使用正电子湮灭寿命和多普勒展宽技术探测了复合材料的缺陷和微观结构变化。随着WO浓度的增加，屏蔽性能和热稳定性得到改善，但一些机械性能，特别是断裂伸长率却下降。WO 的贡献对于降低相对自由体积分数有很强的作用，这反过来又有助于增加复合材料的 γ 射线吸收。建议使用 50–70% WO/PVA 复合材料。