温度不变的多功能体的无压接,基于氧基功能化化纳米板和双功能的单甲胺交叉链接器
Chaochao Cao1,2, Jingwen Yang2,3, Shaobo Yang2,3
1Hebei Key Laboratory of Functional Polymers, School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|May 22, 2024
概括
研究人员开发了一种新方法来制造密集的六角化 (h-BN) 陶. 这种无压接策略使用交联化纳米板 (BNNSs) 进行极端条件应用.
科学领域:
- 材料科学 材料科学 材料科学
- 陶工程 陶工程 陶工程
- 纳米技术 纳米技术
背景情况:
- 大量六角化 (h-BN) 陶由于其高温耐用性和低热膨胀性,具有极端条件应用的潜力.
- 将h-BN粉末烧结成散装陶是具有挑战性的,原因是由于缓慢的自我扩散和材料惰性造成的高能量障碍.
- 开发生产密集,结构坚固的h-BN陶的简单方法对于释放它们的多功能能力至关重要.
研究的目的:
- 从化纳米板 (BNNSs) 开发一种新的无压接策略,以制造大量的h-BN陶.
- 通过采用交叉连接方法来克服与h-BN相关的烧结挑战.
- 研究由此产生的BNNSs交错陶的结构,机械和热力学特性.
主要方法:
- 使用基功能化BNNSs (BNNSs-OH) 采用交联和无压接策略.
- 双功能单乙胺 (MEA) 被用作交叉链接剂,通过化和协调形成B─O─H2C─H2C─H2N:→B<键桥.
- 该方法促进了形成结晶良好的和密集的B-N共价接框架.
主要成果:
- 准备好的BNNSs交织陶达到至少1.2gcm-3.3的密度.
- 陶表现出了卓越的机械强度,弹性和出色的热力学稳定性.
- 记录了超低的线性热膨胀 (0.06 ppm °C−1) 和高的热扩散系数 (4.76 mm2 s−1 在 25 °C,3.72 mm2 s−1 在 450 °C).
结论:
- 开发的战略通过多步物理化学反应有效降低了h-BN烧结的能量障碍.
- 这种方法产生了大量的h-BN陶,具有优越的性能,适合苛刻的应用.
- 这些发现为在广泛的温度范围内更广泛地探索多功能h-BN陶铺平了道路.
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