title: Fabrication and processing of high-strength densely packed carbon nanotube yarns without solution processes.
abstract: Defects of carbon nanotubes, weak tube-tube interactions, and weak carbon nanotube joints are bottlenecks for obtaining high-strength carbon nanotube yarns. Some solution processes are usually required to overcome these drawbacks. Here we fabricate ultra-long and densely packed pure carbon nanotube yarns by a two-rotator twisting setup with the aid of some tensioning rods. The densely packed structure enhances the tube-tube interactions, thus making high tensile strengths of carbon nanotube yarns up to 1.6 GPa. We further use a sweeping laser to thermally treat as-produced yarns for recovering defects of carbon nanotubes and possibly welding carbon nanotube joints, which improves their Young's modulus by up to ∼70%. The spinning and laser sweeping processes are solution-free and capable of being assembled together to produce high-strength yarns continuously as desired.
authors.affiliation: State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics and Tsinghua-Foxconn Nanotechnology Research Center, Tsinghua University, Beijing 100084, China. kliu81@gmail.com
authors.forename: Kai
authors.initials: K
authors.lastname: Liu
authors.forename: Feng
authors.initials: F
authors.lastname: Zhu
authors.forename: Liang
authors.initials: L
authors.lastname: Liu
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Sun
authors.forename: Shoushan
authors.initials: S
authors.lastname: Fan
authors.forename: Kaili
authors.initials: K
authors.lastname: Jiang
mesh_terms: D055119:Elastic Modulus; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry*; D013718:Tensile Strength
chemical_list: D037742:Nanotubes, Carbon; D012996:Solutions