Department of Industrial and Manufacturing Engineering, FAMU-FSU College of Engineering, High-Performance Materials Institute, Florida State University, 2525 Pottsdamer Street, Tallahassee, Florida 32310, USA.
ACS Appl Mater Interfaces. 2013 Aug 28;5(16):8173-8. doi: 10.1021/am4022686. Epub 2013 Aug 19.
Individual carbon nanotube (CNT) exhibits extraordinary mechanics. However, the properties of the macroscopic CNT-based structure, such as CNT fibers and films, are far lower than that of individual CNT. One of the main reasons is the weak interaction between tubes and bundles in the CNT assemblies. It is understood that the cross-links in CNT assembly play a key role to improve the performance of CNT-based structure. Different approaches have been taken to create CNT joints. Most of these approaches focus on connecting CNTs by generating new covalent bonding between tubes. In this work, we intend to reinforce the CNT network by locking the contacted CNTs. Polyacrylonitrile (PAN) was used as precursor because PAN can form graphitic structures after carbonization. The freestanding superthin CNT sheet and CNT yarn were used to evaluate the effects of the PAN precursor to form cross-links between CNTs. The tensile strength of CNT yarn is improved when the yarn is partially infiltrated with PAN and consequently carbonated. High-resolution transmission electron microscopy observation of the sheets shows that graphite structures are formed and cross-link CNTs in CNT assembly.
单根碳纳米管（CNT）表现出非凡的力学性能。然而，宏观 CNT 基结构的性能，如 CNT 纤维和薄膜，远低于单根 CNT。主要原因之一是 CNT 组装体中管与束之间的弱相互作用。据了解，CNT 组装体中的交联在提高 CNT 基结构的性能方面起着关键作用。已经采取了不同的方法来制造 CNT 接头。这些方法大多集中在通过在管之间生成新的共价键来连接 CNT。在这项工作中，我们打算通过锁定接触的 CNT 来增强 CNT 网络。使用聚丙烯腈（PAN）作为前体，因为 PAN 在碳化后可以形成石墨结构。使用独立的超薄 CNT 片和 CNT 纱线来评估 PAN 前体在 CNT 之间形成交联的效果。当纱线部分渗透 PAN 并随后碳化时，CNT 纱线的拉伸强度得到提高。对薄片的高分辨率透射电子显微镜观察表明，在 CNT 组装体中形成了石墨结构并交联 CNT。
