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原子氧诱导的表面侵蚀行为和通过反应分子动力学模拟对聚乙烯基的机械降解

Guixiang Li¹, Junjie Wang¹, Bo Niu¹

¹Key Laboratory of Specially Functional Polymeric Materials and Related Technology (Ministry of Education), East China University of Science and Technology, Shanghai 200237, China.

The journal of physical chemistry. B

|June 8, 2023

概括

原子氧 (AO) 在太空中降解聚合物. 这项研究揭示了AO如何影响聚乙烯 (PEEK),显示侧组增强AO抗性和机械性能.

科学领域:

材料科学材料科学材料科学
太空环境工程太空环境工程
聚合物化学聚合物化学

背景情况:

原子氧 (AO) 对太空环境中的聚合物构成重大威胁.
了解像聚乙烯基 (PEEK) 这样的材料中AO诱导的降解机制对于航天器寿命至关重要.
目前对AO和聚合物之间原子级相互作用的知识有限.

研究的目的:

系统地评估PEEK在高速AO冲击下的侵蚀和机械降解.
在原子尺度上研究在AO碰撞时的PEEK的相互作用机制和局部演变.
探索提高PEEK对AO的抗性和改善其机械性能的策略.

主要方法:

使用反应分子动力学模拟来模拟超高速AO对PEEK的影响.
模拟包括不同的AO流和冲击角度,以评估侵蚀机制.
在改造的PEEK链上进行了高拉伸率的拉伸模拟,以评估机械性能.

主要成果:

AO通过散射或吸附与PEEK相互作用,导致退化物种 (O2,OH,CO,CO2) 的演化.
高能量的AO碰撞转移动能,导致质量损失和表面透;垂直撞击导致的侵蚀比斜撞击少.
用侧基功能化的PEEK链在高温 (300K和800K) 时显著改善了AO电阻和机械性能.

结论:

该研究提供了对AO-PEEK相互作用的原子级洞察力,澄清了降解途径.
将PEEK与侧基功能化是一种有前途的战略,用于开发具有增强空间环境耐受性的材料.
这项研究提供了一种用于太空应用的新型聚合物设计的协议,具有卓越的AO电阻.

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