Morphological and Electrical Properties of Multi-Walled Carbon Nanotube-based Fiber Using General Wet-spinning and Alkaline Post-treatment Methods

In this study, we report the structural features and electrical properties of a multi-walled carbon nanotube (MWCNT)-based fibers, composed entirely of MWCNTs or a large fraction of MWCNTs, using traditional fiber-manufacturing techniques inspired from classical methods applied in the creation of polyester or nylon microfibers. To obtain the MWCNT-based fibers used in this study, as-spun fibers designed to achieve 20 wt% poly(ethylene glycol)-functionalized MWCNTs and 80 wt% alkali-soluble elastomeric copolyester were prepared using a conventional wet-spinning process, and the copolyester was then sequentially removed from the as-spun fiber through an alkaline post-treatment process. As a result, we obtained a final unique MWCNT-based fiber with a MWCNT content of close to 80 wt%. The results of a morphological characterization show clearly that the surface of the fiber is mostly composed of MWCNTs with a compact structure. In addition, the MWCNT-based fiber exhibited an improved electrical conductivity of 1.9×102 S/cm, which is similar to the results of the pure or neat MWCNT-based fibers that we previously investigated. Overall, it was confirmed that the traditional approach for MWCNT-based fibers on this study have a significant potential for producing MWCNT-based fibers close to pure or neat MWCNT fibers even when using general fiber-manufacturing techniques.