Liu Ni, Wang Hui, Wang Shun, Xu Baosheng, Qu Lijie
Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China.
Beijing Key Laboratory of Lightweight Multi-Functional Composite Materials and Structures, Beijing Institute of Technology, Beijing 100081, China.
Polymers (Basel). 2022 Oct 15;14(20):4343. doi: 10.3390/polym14204343.
Endowing epoxy resin (EP) with prospective liquid oxygen compatibility (LOC) as well as enhanced ultra-low-temperature mechanical properties is urgently required in order to broaden its applications in aerospace engineering. In this study, a reactive phosphorus/nitrogen-containing aromatic ethylenediamine (BSEA) was introduced as a reactive component to enhance the LOC and ultra-low-temperature mechanical properties of an EP/biscitraconimide resin (BCI) system. The resultant EP thermosets showed no sensitivity reactions in the 98J liquid oxygen impact test (LOT) when the BSEA content reached 4 wt% or 5 wt%, indicating that they were compatible with liquid oxygen. Moreover, the bending properties, fracture toughness and impact strength of BSEA-modified EP were greatly enhanced at RT and cryogenic temperatures (77 K) at an appropriate level of BSEA content. The bending strength (251.64 MPa) increased by 113.67%, the fracture toughness (2.97 MPa·m) increased by 81.10%, and the impact strength (31.85 kJ·m) increased by 128.81% compared with that of pure EP at 77 K. All the above results demonstrate that the BSEA exhibits broad application potential in liquid oxygen tanks and in the cryogenic field.
为了拓宽环氧树脂（EP）在航空航天工程中的应用，迫切需要赋予其预期的液氧相容性（LOC）以及增强的超低温力学性能。在本研究中，引入了一种含反应性磷/氮的芳香族乙二胺（BSEA）作为反应性组分，以提高EP/双柠康酰亚胺树脂（BCI）体系的LOC和超低温力学性能。当BSEA含量达到4 wt%或5 wt%时，所得的EP热固性材料在98J液氧冲击试验（LOT）中未表现出敏感反应，表明它们与液氧相容。此外，在适当的BSEA含量水平下，BSEA改性的EP在室温（RT）和低温温度（77K）下的弯曲性能、断裂韧性和冲击强度都得到了极大提高。与77K下的纯EP相比，弯曲强度（251.64MPa）提高了113.67%，断裂韧性（2.97MPa·m）提高了81.10%，冲击强度（31.85kJ·m）提高了128.81%。上述所有结果表明，BSEA在液氧罐和低温领域具有广阔的应用潜力。
