石墨烯增强PEEK纳米复合材料中的传热机制
Dongyu Li1, Tong Li1, Zebei Mao1
1Department of Engineering Mechanics, Dalian University of Technology Dalian Liaoning 116024 China tong@dlut.edu.cn +86-411-84706036.
RSC advances
|September 18, 2023
概括
用石墨烯增强的聚合物具有较低的导热性. 这项研究表明,石墨烯层数和PEEK分子定向显著影响热传递,优化热性能.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 纳米技术纳米技术
背景情况:
- 石墨烯具有异常高的导热率 (3000-5000 W m-1 K-1),非常适合用于热管理应用.
- 然而,用石墨烯增强的聚合物具有显著较低的导热率 (<10 W m-1 K-1),远远低于理论预测.
- 了解这些复合材料的传热机制对于实现它们的全部潜力至关重要.
研究的目的:
- 为了研究石墨烯添加对聚乙 (PEEK) 纳米复合材料的导热性的影响.
- 阐明在石墨烯-PEEK系统中控制热传递的关键因素.
- 为设计高性能导热聚合物复合材料提供见解.
主要方法:
- 利用分子动力学 (MD) 模拟来分析石墨烯-PEEK纳米复合材料中的热传递.
- 检查了石墨烯层数,屈曲角度和层间距离对导热性的影响.
- 研究了PEEK分子链结构,特别是环方向在热传输中的作用.
主要成果:
- 在PEEK纳米复合材料中的导热增强取决于石墨烯含量和PEEK分子结构.
- 在PEEK的环和热流方向之间的角度极大地影响热导率.
- 增加石墨烯层与改善的导热率有积极的相关性.
- 当石墨烯层均,层间距离最小 (小于截断半径) 时,就会发生最佳的导热增强.
结论:
- 仅仅是石墨烯含量并不决定PEEK纳米复合材料的导热性;结构因素同样重要.
- 与热流方向相比,PEEK分子链的方向在热传输中起着重要作用.
- 优化石墨烯层堆叠和最小化层间距离是提高石墨烯-PEEK复合材料热导率的关键策略.
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