不敏感的丰富的氨胺能量材料的爆炸性能根据第一原则预测反应分子动力学模拟
Dezhou Guo1, Yuanyuan Wei1, Sergey V Zybin2
1State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
JACS Au
|April 26, 2024
概括
研究人员探索了来自FOX-7的新能量材料. 他们发现,在FOX-7-T中用四醇环取代一个基组,由于分解路径和产品形成的改变,会降低引爆性能.
科学领域:
- 能量材料科学 能量材料科学
- 计算化学的计算化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 1,1-米诺-2,2-丁乙烯 (FOX-7) 是一种有价值的能量材料 (EM),因为它具有高爆炸性和低灵敏性的平衡.
- 开发FOX-7衍生物是可取的,但许多具有高灵敏度,限制了它们的实际应用.
- 1,1-米诺-2-二二乙烯 (FOX-7-T),一种带有二环的衍生物,具有良好的稳定性,但意外地比FOX-7具有较低的引爆性能.
研究的目的:
- 与FOX-7相比,调查FOX-7-T爆炸性能降低和不敏感的原子学原因.
- 了解功能组在这些能量材料的初始分解反应中的作用.
- 为设计下一代高能能量材料提供见解.
主要方法:
- 使用ReaxFF反应力场的反应分子动力学 (RxMD) 模拟.
- 联合量子力学和分子动力学 (QM-MD) 模拟.
- 基于第一原则的模拟来预测爆炸参数.
主要成果:
- 最初的分解机制在FOX-7和FOX-7-T之间显著不同.
- 福克斯-7通过转移分解,而福克斯-7-T在较低的温度下经历四环分解,形成N2并启动后续反应.
- 模拟预测FOX-7-T与FOX-7相比,计算的Chapman-Jouguet (CJ) 压力,爆炸速度和CJ温度要低得多.
- 在FOX-7-T中减少的能量传递归因于凝结相碳集群的形成,阻碍了CO2和N2.2等气体产物的产生.
结论:
- 功能组显著影响FOX-7衍生物的分解途径和能量性能.
- 在FOX-7-T中,四醇环导致能量释放效率较低,与FOX-7中的基组相比.
- 氧气平衡是设计具有最佳性能的高能能量材料的关键参数.
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