A research team, led by Prof. HUANG Qunying, from the Institute of Nuclear Energy Safety Technology (INEST), Hefei Institutes of Physical Science (HFIPS), Chinese Academy of Sciences (CAS), recently developed a novel neutron shielding composite.
This composite, called Sm2O3-APTES/AFG-90H, was with high thermal stability, mechanical properties and efficient neutron shielding performance, according to the team, which is important characteristics for neutron shielding materials in advanced nuclear energy systems.
The related research was published in the journal Polymers.
The high dispersion and good compatibility for fillers in polymers can ensure the comprehensive performance of epoxy resin composites.
Therefore, in this research, physicists used new high-performance epoxy resins AFG-90H and Sm2O3 as the matrix and filler, respectively to develop neutron shielding materials with higher performance. They also adopted the coupling agents (APTES) to modify the surface of Sm2O3 to improve the dispersion and compatibility of particles in AFG-90H resins.
Scientists conducted a series of comprehensive experiments to check the physical properties of the composite, in which the Monte Carlo particle transport software SuperMC was used to optimize the compositions to get high shielding efficiency.
After testing the initial thermal decomposition temperature, glass transition temperature and Young's modulus of the composite with 30wt% Sm2O3-APTES addition, they found the results were significantly improved compared with the AFG-90H matrix. For low Sm2O3-APTES addition, some of the residual stress in the composite could be dispersed by Sm2O3-APTES. For high Sm2O3-APTES addition, a large amount of local plastic deformation occurred near the equator of Sm2O3-APTES aggregates, resulting in the dissipation of the binding energy combined between the fillers and AFG-90H matrix.
The results provided new ideas for the R&D of high-performance neutron shielding materials in advanced nuclear energy systems.
This work was supported by the Key R&D Project of the Ministry of Science and Technology of China.
Figure 1 Thermal performance curves: (a) TG; (b) DTG; (c) DSC and (d) Tg of Sm2O3-APTES/AFG-90H. (Image by WANG Hongqing)
Figure 2 SEM images of tensile fracture surfaces for composites with different Sm2O3-APTES contents: (a–f): 0, 5, 10, 15, 20 and 30 wt%. (Image by WANG Hongqing)