微观化学反应机制和Al/PTFE的动力模型
Mengmeng Guo1, Xiangrong Li2, Yongkang Chen2
1State Key Labratory of Explosive Science and Technology, Beijing Institute of Technology, Beijing 100081, China.
Polymers
|June 19, 2024
概括
氧化物层的厚度显著影响/聚四乙烯 (Al/PTFE) 的反应. 5 Å 的氧化层促进了反应剂扩散和核心反应,而 10 Å 的氧化层显示了接口反应和氧化层迁移.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 计算化学计算化学
背景情况:
- /聚四乙烯 (Al/PTFE) 是一种反应性材料系统.
- 了解其微观反应机制对于控制能量释放至关重要.
- 氧化物层的特性可以影响高能材料的反应性.
研究的目的:
- 研究Al/PTFE的微观反应机制和运动模型.
- 分析氧化物层厚度对Al/PTFE热化学行为的影响.
- 确定Al/PTFE反应的动力参数 (激活能量和预指数因子).
主要方法:
- 使用反应力场 (ReaxFF) 对具有不同氧化物层厚度 (0 Å,5 Å,10 Å) 的Al/PTFE接口模型进行模拟.
- 同时热分析 (TG-DSC) 用于研究不同加热速率的热化学行为.
- 使用收缩体积 (R3) 和三维扩散 (D3) 模型进行动力分析.
主要成果:
- 氧化物层的厚度显著影响了Al/PTFE反应过程.
- 5 Å 氧化层允许反应剂扩散和核心反应; 10 Å 层显示接口反应和氧化层运动.
- 该研究获得了机制函数,并确定了激活能量 (258.8 kJ/mol) 和预指数因子 (2.495 × 10^15 min^-1).
结论:
- 氧化物层的厚度是Al/PTFE反应性的关键因素.
- 这些发现为Al/PTFE的微观反应路径和宏观能量释放提供了洞察力.
- 这项研究为了解和量化Al/PTFE反应性材料的行为提供了理论意义.
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