US 12,151,939 B2
Carbon nanotube fiber having improved physical properties and method for manufacturing same
Bon Cheol Ku, Wanju-Gun (KR); Jun Yeon Hwang, Wanju-Gun (KR); Hyeon Su Jeong, Wanju-Gun (KR); Nam Ho You, Wanju-Gun (KR); Nam Dong Kim, Wanju-Gun (KR); Dae Yoon Kim, Wanju-Gun (KR); Dong Ju Lee, Wanju-Gun (KR); Seo Gyun Kim, Wanju-Gun (KR); Seung Ki Hong, Wanju-Gun (KR); and Seung Woo Ryu, Seoul (KR)
Assigned to KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed by KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed on Jul. 28, 2021, as Appl. No. 17/387,305.
Claims priority of application No. 10-2021-0006762 (KR), filed on Jan. 18, 2021.
Prior Publication US 2022/0227631 A1, Jul. 21, 2022
Int. Cl. C01B 32/168 (2017.01); D01D 5/12 (2006.01); D01F 9/12 (2006.01)
CPC C01B 32/168 (2017.08) [D01D 5/12 (2013.01); D01F 9/12 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method for manufacturing a carbon nanotube fiber, the method comprising the steps of:
liquid crystal spinning carbon nanotubes with a purity of 90% by weight or more to obtain a first carbon nanotube fiber; and
heat-treating the first carbon nanotube fiber at 2,200 to 3,000° C. under an inert gas atmosphere to obtain a second carbon nanotube fiber;
wherein the second carbon nanotube fiber has a density of 1.0 to 2.5 g/cm3;
wherein the carbon nanotubes include 20 to 100% by weight of double-walled carbon nanotubes;
wherein the second carbon nanotube fiber has a carbon nanotube diameter of 1.02 to 1.5 times that of the first carbon nanotube fiber;
wherein the second carbon nanotube fiber has a specific tensile modulus of 2 to 10 times that of the first carbon nanotube fiber; and
wherein the second carbon nanotube fiber has a thermal conductivity of 1.1 to 3 times that of the first carbon nanotube fiber.