在聚烯化成碳纤维过程中形成波形石墨烯状网络
Toru Ishikawa1, Fumihiko Tanaka1,2, Kosuke Kurushima3
1Composite Materials Research Laboratories, Toray Industries, Inc., 1515 Tsutsui, Masaki-cho, Iyo-gun, Ehime 791-3193, Japan.
Journal of the American Chemical Society
|May 30, 2023
概括
基于聚烯的碳纤维 (PAN-CF) 具有优越的强度,这是由于其在高温热解过程中形成的独特波状石墨烯状网络 (WGN) 结构. 这种非晶体WGN结构增强了抗破裂和抗拉强度,优于脆性基碳纤维.
科学领域:
- 材料科学
- 纳米技术
- 化学工程
背景情况:
- 聚烯基基碳纤维 (PAN-CF) 与金属和基碳纤维 (pb-CF) 相比具有更好的机械性能.
- 在热解过程中,PAN-CF的原子结构和形成机制尚不清楚.
- PAN-CF的高拉伸强度 (7GPa) 是由于其独特的结构,与pb-CF的脆性形成鲜明对比.
研究的目的:
- 阐明PAN-CF在热解过程中的原子结构和形成过程.
- 研究材料结构与其特殊机械性能之间的关系.
- 将PAN-CF的结构特性与pb-CF的结构特性进行比较.
主要方法:
- 在碳纳米管中对烯酸-9-mer进行热解.
- 使用原子分辨率电子显微镜和拉曼光谱仪进行现场监测.
- 微观分析以确定环状结构和材料形态.
主要成果:
- 在缓慢石墨化 (900-1800 °C) 过程中在1200-1400 °C形成热反应波形石墨烯状网络 (WGN).
- WGN结构包括5个,6个和更大的环,导致非平面,波形形态.
- 层次上堆叠的WGN层形成了一个互数字化的非晶体相,增强了断裂阻力和拉伸强度.
结论:
- 独特的波状石墨烯状网络 (WGN) 结构是PAN-CF高拉伸强度和抗破裂的原因.
- PAN-CF的非晶体结构类似于高材料,有助于其卓越的性能.
- 这些发现为PAN-CF制造及其高级应用潜力提供了关键的见解.
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