Dry spinning yarns from vertically aligned carbon nanotube arrays produced by an improved floating catalyst chemical vapor deposition method

Carbon nanotube (CNT) yarn was drawn directly from super aligned CNT arrays synthesized by an improved floating catalyst chemical vapor deposition method. The synthesis of aligned CNT was performed as a multi-step interim reactant supply reaction to produce a double-layered CNT array in a horizontal quartz tube reactor. During the growth period, most impurities were blocked on the top surface of the first layer and therefore the top aligned CNT layer was unspinnable. However, the bottom CNT layer was super aligned CNTs, which were with clean surface and a tortuosity factor of 1.07. During the dry spinning process, the tangles, friction, and van der Waals interaction between CNTs served to hold them into CNT yarns. The tensile strength of the as-obtained CNT yarn can be further improved from 0.24 to 0.30 GPa by twisting.