Surface modification of samarium oxide (Sm2O3) fillers and their corresponding morphological, wear, and mechanical properties of Sm2O3/UHMWPE composites

Effective and improved neutron-shielding materials are considered necessary measures to protect and/or reduce risks of receiving excessive doses of neutrons in radiation-related workers and the general public, of which neutron technologies are presently utilized in various applications. As a result, this research aimed to develop novel and superior neutron-shielding materials based on the addition of samarium oxide (Sm2O3) as a high-performance neutron protective filler in ultra-high-molecular-weight polyethylene (UHMWPE) composites. However, due to poor interfacial compatibility between inorganic and organic substances (Sm2O3 and UHMWPE, respectively, in this case), decreases in overall mechanical and wear properties of the composites were possible. To avoid the drawbacks of Sm2O3/UHMWPE composites, surface modification of Sm2O3 particles was carried out using 3-aminopropyltriethoxy silane coupling agent (KBE903) with different concentrations of 5, 10, and 20%wt. The modified Sm2O3 particles were then added to UHMWPE with the investigated content of 25%wt. The results of Fourier transform infrared (FTIR) spectroscopy indicated that Sm2O3 particles were successfully modified using KBE903 silane coupling agent, and the treatment of 10%wt. KBE903 led to increases of tensile strength, elongation at break and hardness of Sm2O3/UHMWPE composites in comparison with other concentrations of KBE903. In addition, wear rates and surface roughness of 10%wt-KBE903 were also the highest among all investigated concentrations due to the highest formation of crystallinity (86.73%) determined using X-ray diffraction (XRD). For scanning electron microscopy (SEM) determination, the results revealed that the utilization of 10%wt-KBE903 in Sm2O3 particles reduced phase separation and particle agglomeration in the composites, This resulted in decreases of self-polymerization and oligomer of Sm2O3 particles that actually led to less wear tracks on the surface and better particle dispersion of Sm2O3 particles in UHMWPE composites.