基于分子动力学模拟的卡普顿型聚胺原子氧侵蚀保护的机制分析和潜在应用
Shengrui Zhou1, Li Zhang1, Liang Zou1
1School of Electrical Engineering, Shandong University, Jinan 250061, China.
Polymers
|June 27, 2024
概括
聚胺复合材料为航空航天提供了增强的原子氧 (AO) 侵蚀性. PI/POSS复合材料通过SiO2层显示出优越的保护,而化聚胺 (FPI) 则提供了显著的热稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 航空航天工程 航空航天工程
- 计算化学的计算化学
背景情况:
- 聚胺 (PI) 由于其特性,对航空航天至关重要.
- 在低地球轨道 (LEO) 中的原子氧 (AO) 会导致PI的显著降解.
- 发展 AO 耐侵蚀性对于航天器的寿命至关重要.
研究的目的:
- 为了研究化聚胺 (FPI) 和多面寡合物丝素 (POSS) 复合聚胺模型的 AO 侵蚀性.
- 在分子水平上分析这些材料的保护机制.
- 为设计先进的AO侵蚀防护系统提供见解.
主要方法:
- 使用了反应分子动力学 (MD) 模拟.
- 模拟分析了AO与PI,FPI和PI/POSS复合模型的相互作用.
- 材料降解和保护层的形成被观察到超过35 ps.
主要成果:
- 该PI/POSS复合材料表现出最高的AO侵蚀性,保持其质量的84.1%.
- 在PI/POSS上形成了一层保护性SiO2碳化层,阻断了AO和热量.
- 由于 -CF3组增强了热稳定性,FPI表现第二好,保留了80.7%的质量.
结论:
- PI/POSS复合材料通过自成型保护层提供优质的AO侵蚀保护.
- FPI提供了增强的热稳定性,有助于改善AO电阻.
- 分子动力学模拟为航空航天材料设计有效的AO保护策略提供了宝贵的见解.
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