聚合后修饰以合成性和异性聚烯合物和相关碳纤维
Tarryn C Trick1, Sheila L Tran1, Brent W Harfmann1
1Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States.
Journal of the American Chemical Society
|August 20, 2025
概括
这项研究引入了通过立体控制的聚合物合成的同位素多烯 (iPAN). 与传统的PAN纤维相比,由此产生的基于iPAN的碳纤维具有显著的拉伸强度和模量.
科学领域:
- 聚合物化学
- 材料科学
- 纳米技术
背景情况:
- 聚烯 (PAN) 是90%以上的碳纤维的主要前体.
- 传统的PAN合成缺乏立体化学控制,导致广泛分散并影响CF特性.
- PAN前体的立体化学对于CF的石墨化和最终性质至关重要.
研究的目的:
- 开发一种新方法以控制立体化学合成等离子PAN (iPAN).
- 研究iPAN前体化学对衍生碳纤维特性的影响.
- 提高基于PAN的碳纤维的抗拉强度和模量.
主要方法:
- 一个两步过程,涉及易斯酸催化立体控制的聚合,以形成异性PTBAM (iPTBAM).
- 在聚合后的改造过程中将iPTBAM转化为异烯 (iPAN-TB).
- 将iPAN-TB和控制PAN湿成前体纤维,然后进行高温处理 (250°C和1500°C).
主要成果:
- 合成的iPTBAM具有较低的分散性 (<1.25) 和较高的同位性 (约. 77%的三角形).
- 在 iPAN-TB 中,可达到 78% 的烯胺基转化为烯.
- 与对照PAN纤维相比,iPAN-TB衍生碳纤维在加热后的抗拉强度增加了近六倍,模量增加了四倍,而不会影响伸展性.
结论:
- 通过对iPAN进行立体控制的合成,可以获得先进的碳纤维.
- 基于iPAN的CF的增强机械性能归因于前体化学的改善.
- 这种方法为基于PAN的碳纤维技术带来了重大进步.
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