Data for: Simultaneously enhanced tenacity, rupture work, and thermal conductivity of carbon nanotubes fibers by raising effective tube portion

Although individual carbon nanotubes (CNTs) are superior as constituents to polymer chains, the mechanical and thermal properties of CNT fibers (CNTFs) remain inferior to synthetic fibers due to the failure of embedding CNTs effectively in superstructures. Conventional techniques resulted in a mild improvement of target properties while degrading others. Here, a Double-Drawing technique is developed to rearrange the constituent CNTs in both mesoscale and nanoscale morphology. Consequently, the mechanical and thermal properties of the resulting CNTFs can simultaneously reach their highest performances with specific strength ~3.30 N/tex (4.60 GPa), work of rupture ~70 J/g, and thermal conductivity ~354 W/m/K, despite starting from low-crystallinity materials (IG:ID~5). The processed CNTFs are more versatile than comparable carbon fiber, Zylon and Dyneema. Based on evidence of load transfer efficiency on individual CNTs measured with In-Situ-Stretching-Raman, we find the main contributors ..., CNT fibers preparation: Continuous CNTFs were fabricated using the floating catalyst method (1, 2), and supplied by Tortech Nanofibers Ltd. The produced CNT aerogels from a tube furnace were mechanically pulled out, densified by acetone, and spun continuously winded. Although a small tension force is applied during the spinning process to obtain a preferential alignment along fiber axis, the anisotropic ratio is always within 0.85 (3).
Enhancing CNTF with the Double-Drawing process: (i) Immersing and first drawing: The raw CNTF is fixed at its lower end inside a dropping funnel, and its upper end fixed on a spin rotor. The CNTF is straightened out but without a pre-tension. After being immersed in chlorosulfonic acid (CSA), CNTF is firstly drawn to a specific ratio (ηCSA); (ii) Poisson Tightening: After the immersing solvent being changed into chloroform, the CNTF is immediately further drawn by ηPT. (iii) Rinsing: after the Double-Drawing processes, the CNTF is successively rinsed in w...,