Sustained Growth of Ultralong Carbon Nanotube Arrays for Fiber Spinning

摘要

Carbon nanotubes (CNTs) arc the strongest materials ever discovered by mankind. With measured tensile strengths as high as 150 GPa and a high modulus of 1 TPa. CNTs are very promising for many high-strength, lightweight applications. Several approaches have been reported to process micrometer-long CNTs into fibers, including dispersing CNTs into polymer or acid solutions and then spinning them into composite or pure CNT fibers. Unfortunately, difficulties in CNT dispersion and alignment have hindered the full utilization of CNT strength. Recently, CNT yarns have been directly spun from CNT arrays. This new approach has the advantage of good CNT alignment and high CNT volume fraction, and therefore is very promising for producing higher strength CNT yarns and fibers. So far, CNT fibers can only be spun from CNT arrays that are less than 300 urn long, and this has limited their tensile strengths to only a few hundred MPa. Therefore, it is critical to synthesize spinnable long CNT arrays so that higher strength can be obtained in the spun CNT fibers.