Surfactant-free spinning of composite carbon nanotube fibers

Fibers and yams are promising forms to use and control the spatial orientation of carbon nanotubes in macroscopic materials. Various approaches have been proposed in the last few years to achieve fibers with a fraction of carbon nanotubes. Among them, coagulation spinning in aqueous media has proven to be a simple and capable method of leading to super-tough materials. However, all water-based processes described so far have made use of surfactant-stabilized carbon nanotubes. In the present work, a method is shown to spin fibers from surfactant-free nanotube solutions while preserving an all water-based process. The resultant fibers exhibit mechanical and electrical properties that compare well with those of previously reported fibers spun with surfactants. The fibers exhibit a significant toughness and a high electrical conductivity.