Lee, Dong-Myeong Park, Junbeom Lee, Jaegeun Lee, Sung-Hyun Kim, Shin-Hyun Kim, Seung Min Jeong, Hyeon Su 2024-01-19T15:32:04Z 2024-01-19T15:32:04Z 2021-09-02 2021-02 0008-6223 https://pubs.kist.re.kr/handle/201004/117461 We present a post-treatment method for directly-spun ultra-thick carbon nanotube fibers (CNTFs) with a high linear density of similar to 6 tex (g km(-1)), which can possibly meet industrial-scale productivity. The treatment consists of consecutive steps of swelling of CNTFs in chlorosulfonic acid, stretching, and coagulation. The swelling of CNTFs makes even distribution of the CNT bundles, which are the subunits of CNTFs, and thereby promotes the removal of the interstitial voids and macroscopic pores during subsequent coagulation. The stretching straightens tortuous CNT bundles, and thereby facilitates dense packing of aligned bundles along the fiber axis that are evenly distributed by swelling. However, highly-tortuous CNT bundles in the high linear-density CNTF leads to incremental improvement of structure and properties. The stretching is only effective at stretching ratio (R-S) > 20%, and both tensile strength and electrical conductivity gradually increase as R-S increases, to 27- and 8.7-times at the maximum R-S = 100%. We believe that our study on the influence of R-S on the structure and properties of high linear-density CNTFs provide a new opportunity for designing the industrial process of the post-treatment to commercialize CNTFs. (C) 2020 Elsevier Ltd. All rights reserved. English Pergamon Press Ltd. Improving mechanical and physical properties of ultra-thick carbon nanotube fiber by fast swelling and stretching process Article 10.1016/j.carbon.2020.10.068 1 Carbon, v.172, pp.733 - 741 Carbon 172 733 741 N scie scopus 000600196000006 2-s2.0-85095761869 Chemistry, Physical Materials Science, Multidisciplinary Chemistry Materials Science Article STRENGTH CONDUCTIVITY INFILTRATION ENHANCEMENT YARN Carbon nanotube fiber High linear density Direct spinning Densification process Mechanical and electrical properties