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This work reports on the simulated neutron and self-emitted gamma attenuation of ultra-high-molecular-weight polyethylene (UHMWPE) composites containing varying Sm2O3 contents in the range 0–50 wt.%, using a simulation code, namely MCNP-PHITS. The neutron energy investigated was 0.025 eV (thermal neutrons), and the gamma energies were 0.334, 0.712, and 0.737 MeV. The results indicated that the abilities to attenuate thermal neutrons and gamma rays were noticeably enhanced with the addition of Sm2O3, as seen by the increases in µm and µ, and the decrease in HVL. By comparing the simulated neutron-shielding results from this work with those from a commercial 5%-borated PE, the recommended Sm2O3 content that attenuated thermal neutrons with equal efficiency to the commercial product was 11–13 wt.%. Furthermore, to practically improve surface compatibility between Sm2O3 and the UHMWPE matrix and, subsequently, the overall wear/mechanical properties of the composites, a silane coupling agent (KBE903) was used to treat the surfaces of Sm2O3 particles prior to the preparation of the Sm2O3/UHMWPE composites. The experimental results showed that the treatment of Sm2O3 particles with 5–10 pph KBE903 led to greater enhancements in the wear resistance and mechanical properties of the 25 wt.% Sm2O3/UHMWPE composites, evidenced by lower specific wear rates and lower coefficients of friction, as well as higher tensile strength, elongation at break, and surface hardness, compared to those without surface treatment and those treated with 20 pph KBE903. In conclusion, the overall results suggested that the addition of Sm2O3 in the UHMWPE composites enhanced abilities to attenuate not only thermal neutrons but also gamma rays emitted after the neutron absorption by Sm, while the silane surface treatment of Sm2O3, using KBE903, considerably improved the processability, wear resistance, and strength of the composites.

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This work investigated the cure characteristic, physical mechanical properties, and tribology behavior of carbon black filled acrylonitrile butadiene rubber composites using multi-walled carbon nanotubes as co-reinforcing additive in various contents from 0, 3, 6, 9, and 15 parts per hundred rubbers. The physical and tribological behavior was also observed in large-scale piston driven hydraulic apparatus which was specially designed for seal applications. The results suggested that the modulus and hardness were found to increase after adding multi-walled carbon nanotube whereas the tensile and tear strength were not significantly affected. Adding multi-walled carbon nanotube was found to increase the bound rubber and crosslink density. For ball-on-disc tribo-testing, it was found that the coefficient of friction of the rubber composites decreased with multi-walled carbon nanotube content and the applied loads whereas the specific wear rate was more influenced by the applied loads used. Finally, under the large-scale piston driven hydraulic test apparatus in comparison with commercial grade rubber seals, it was found that the weight loss for the acrylonitrile butadiene rubber composites with multi-walled carbon nanotube was much lower than that without multi-walled carbon nanotube. The carbon black/acrylonitrile butadiene rubber composites with 9–12 parts per hundred rubbers multi-walled carbon nanotube were recommended as the most suitable for hydraulic seal applications.