Preparation of Micron Plate Sm2O3 Fillers Reinforced High-density Polyethylene Composites for Neutron and Gamma Radiation Shielding

Samarium oxide (Sm2O3)/boron carbide (B4C)/high-density polyethylene (HDPE) composites are respectively prepared by using synthesized Sm2O3 fillers (Sm2O3-I) and commercial Sm2O3 fillers (Sm2O3-II) for neutron and gamma radiation shielding. The X-ray-ray diffraction (XRD) patterns reveal that the phase of Sm2O3-I fillers is a cubic crystal system, , body-centered cubic lattices, and its space group is Ia (3) over bar (206) . However, Sm2O3-II fillers have two phases. One is a monoclinic crystal system, simple monoclinic lattices, and its space is C2/m (12). The other one is a cubic crystal system, body-centered cubic lattices, and the space group is Ia (3) over bar (206) . Field emission scanning electron microscopy(FESEM) (FESEM) and specific surface area analyses reveal that the micromorphology of Sm2O3-I2O3-I fillers is micron plate with silt and its Brunauer-Emmett-Teller(BET)-Emmett-Teller (BET) specific surface area (S-BET) is 5.15 m(2)/g, while irregularly shaped Sm2O3-II fillers have two kinds of micromorphology caused by the two phases of Sm2O3-II fillers, which are plate-like agglomeration and agglomeration without specific shape, and the S BET of Sm2O3-I fillers is 2.47 m(2)/g. The melting temperature (T-p) and yield strength (sigma(y)) of the synthesized Sm2O3-I/B4C/HDPE composites are respectively 140.6 degrees C and 22.6 MPa, which are better than the commercial Sm2O3-II/B4C/HDPE composites. The neutron and gamma radiation shielding tests reveal that the synthesized Sm2O3 fillers with even size and high BET-specific surface area can improve the neutron and gamma radiation shielding performance of composites. 10% Sm2O3-I/20%B4C/70%HDPE(mass fraction)) with a thickness of 15 cm has a neutron radiation shielding rate of 98.4% under the Cf-252 neutron source and a gamma radiation shielding rate of 71.7% under Cs-137 gamma source.