Fabrication and mechanical properties of carbon nanotube yarns spun from ultra-long multi-walled carbon nanotube arrays

Carbon nanotube (CNT) yarns have been fabricated by dry spinning from vertically aligned millimeter-long multi-walled carbon nanotube (MWCNT) arrays and their mechanical properties have been studied. By using 2-mm long CNTs and densely packing of CNT yarns we achieved a tensile strength of 1068 MPa and Young’s modulus of 55 GPa. Our CNT yarns have diameters of tens of micrometers being easy to handle and possessing high effective load capacity up to 0.81 N. We discuss mechanical properties of CNT yarns spun from relatively thick MWCNT along with a detailed analysis of various post-spin processes and their effect on CNT yarns characteristics. Also, we point out the difference between mechanical properties of dry spun CNT yarns and conventional spun textile yarns.