Comparisons of enhanced thermal neutron‐ and gamma‐shielding properties in UHMWPE composites containing surface‐treated Sm₂O₃ and Gd₂O₃ particles

Abstract

The rapid development and broad utilization of nuclear technologies has raised safety concerns, especially for those requiring radiation‐shielding equipment. To cope with such high demands and risks, the current study investigated the potential of utilizing ultra‐high‐molecular‐weight polyethylene (UHMWPE) composites containing varying contents of surface‐treated samarium oxide (Sm2O3) or gadolinium oxide (Gd2O3) particles as dual thermal neutron‐ and gamma‐shielding materials. The results showed that the thermal neutron‐ and gamma‐shielding abilities of the composites increased with increasing filler contents, as evidenced by the highest values of μ (in the case gamma rays), ∑t (in the case of thermal neutrons), and μm, as well as the lowest values of HVL and TVL, being achieved in the samples containing 25 wt% Sm2O3 or Gd2O3 (the maximum content investigated). Furthermore, based on the comparative thermal neutron‐shielding properties of the current composites to those of a common shielding product containing 15.9 wt% B2O3 (corresponding to 5 wt% B), the addition of 2.5 wt% Gd2O3 or 4.8 wt% Sm2O3 to the UHMWPE matrix was sufficient to attenuate thermal neutrons with equal efficiency to that of the referenced material. Furthermore, the results indicated that the addition of both fillers increased the density and hardness (Shore D) but reduced the degree of crystallinity, tensile strength, elongation at break, and dielectric strength of the composites, for which the degree of changes in each property largely depended on filler types and contents. In summary, the overall results suggested that both Sm2O3 and Gd2O3 could substantially enhance the thermal neutron‐ and gamma‐shielding properties of the composites, while the developed UHMWPE composites offered durability and excellent electrical properties that could be suitable for use in various applications.

Highly Efficient and Eco-Friendly Thermal-Neutron-Shielding Materials Based on Recycled High-Density Polyethylene and Gadolinium Oxide Composites

“…A Student's t-test was also applied to determine any significant differences between the results of interest. The statistical analyses were conducted using the IBM SPSS Statistics 20 software (New York, NY, USA) [17]. The functional groups of KBE903, non-treated Gd 2 O 3 , and treated Gd 2 O 3 particles, determined using FTIR, are shown in Figure 3.…”

“…The determination of thermal-neutron-shielding parameters consisted of neutron transmission ratios (I/I 0 ), the total macroscopic cross section (Σ t ), the mass attenuation coefficient (∑ t/ρ ), the half-value layer (HVL), and the tenth value layer (TVL). The corresponding equations for the calculations of these parameters as well as the graphical setup of the neutron shielding tests are available elsewhere [17].…”

“…The degrees of crystallinity (%XC) for all Gd 2 O 3 /r-HDPE sampl the plots of XRD (Figure S1), are shown in Table 8, indicating that th deviation) of %XC abruptly increased with the initial addition of 5 w composites (increase from 38.6 ± 4.5% in the pristine r-HDPE to 53.6 ± Gd 2 O 3 /r-HDPE composites) and then slightly decreased at higher cont crease in %XC could have been due to the high crystallinity of Gd 2 O 3 p increased the crystalline phase and subsequently increased the overa posites. However, as more Gd 2 O 3 particles were added to the samples, r-HDPE molecular chains was restricted due to the interference of G retarded the growth in the crystalline phase (hindering the ability of th lar chains to arrange themselves in an ordered crystalline structure) lowered the %XC of the composites [17,56]. It should be noted that th used for %XC calculations were 2θ = 10.3°, 22.4°, 24.8°, 27.6°, 29.4°, 33.…”

“…The initial increase in %XC could have been due to the high crystallinity of Gd 2 O 3 particles that greatly increased the crystalline phase and subsequently increased the overall %XC of the composites. However, as more Gd 2 O 3 particles were added to the samples, the mobility of the r-HDPE molecular chains was restricted due to the interference of Gd 2 O 3 particles that retarded the growth in the crystalline phase (hindering the ability of the r-HDPE molecular chains to arrange themselves in an ordered crystalline structure) and subsequently lowered the %XC of the composites [17,56]. It should be noted that the crystalline peaks used for %XC calculations were 2θ = 10.3 The thermal-neutron-shielding properties of non-aged Gd 2 O 3 /r-HDPE composites with varying Gd 2 O 3 contents and material thicknesses are shown in Figures 8a and 9.…”

“…These materials are suitable for such purposes due to their high contents of lightweight elements, particularly hydrogen (H) and carbon (C), within their chemical compositions. These elements efficiently scatter incoming neutrons, leading to substantial energy losses and necessitating fewer scatters to sufficiently lower neutron intensities compared to those containing heavier elements [17].…”