Method for producing densified carbon nanotube fiber

Patent metadata

Field	Value
Publication number	US-11897770-B2
Application number	US-202017101198-A
Country	US
Kind code	B2
Filing date	Nov 23, 2020
Priority date	Apr 17, 2020
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

Disclosed is a method for mass-producing densified carbon nanotube fiber. The method includes preparing carbon nanotube fiber, swelling the carbon nanotube fiber by applying an acid solution thereto, and stretching the carbon nanotube fiber, coagulating the stretched carbon nanotube fiber so as to remove the acid solution present therein, and drying the coagulated carbon nanotube fiber.

First claim

What is claimed is:

1. A method for producing densified carbon nanotube fiber, the method comprising:
preparing carbon nanotube fiber;
swelling the carbon nanotube fiber by applying an acid solution thereto, and stretching the carbon nanotube fiber;
coagulating the stretched carbon nanotube fiber so as to remove the acid solution present therein; and
drying the coagulated carbon nanotube fiber;
wherein in the preparing the carbon nanotube fiber, carbon nanotube fiber having a linear density equal to or greater than 5 tex is prepared, and
in the swelling and stretching the carbon nanotube fiber, the carbon nanotube fiber is stretched to a stretching ratio greater than 80% but less than or equal to 200%.

2. The method of claim 1 , wherein, in the preparing the carbon nanotube fiber, as-spun carbon nanotube fiber is prepared by a direct spinning method.

3. The method of claim 1 , wherein, in the swelling and stretching the carbon nanotube fiber, the carbon nanotube fiber is immersed in the acid solution.

4. The method of claim 1 , wherein the acid solution is one selected from the group consisting of chlorosulfuric acid (HSO 3 Cl), fluorosulfuric acid (HSO 3 F), trifluoroacetic acid (CF 3 COOH), trifluoromethanesulfonic acid (CF 3 SO 3 H), fluoroantimonic acid (H 2 FSbF 6 ), carborane acid, and combinations thereof.

5. The method of claim 1 , wherein, in the swelling and stretching the carbon nanotube fiber, the carbon nanotube fiber is immersed in the acid solution for 1 minute or longer.

6. The method of claim 1 , wherein, in the swelling and stretching the carbon nanotube fiber, the carbon nanotube fiber is stretched to a stretching ratio greater than 100% but less than or equal to 200%.

7. The method of claim 1 , wherein, in the coagulating the stretched carbon nanotube fiber, the stretched carbon nanotube fiber is coagulated by applying a coagulation solution, selected from the group consisting of diethyl ether, fuming sulfuric acid (oleum) and a combination thereof, to the stretched carbon nanotube fiber.

8. The method of claim 7 , wherein the coagulation solution comprises 50% by weight to 85% by weight of diethyl ether and 15% by weight to 50% by weight of oleum.

9. The method of claim 1 , wherein, in the drying the coagulated carbon nanotube fiber, the coagulated carbon nanotube fiber is dried while applying tension thereto.

Assignees

• Korea Inst Sci & Tech

Inventors

• Jeong Hyeon Su
• Kim Seung Min
• Moon Sook Young
• Lee Dong Myeong

Classifications

• C01B32/168 Primary

  After-treatment · CPC title

• D01D5/0046

  the fibre formed by coagulation, i.e. wet electro-spinning · CPC title

• D01D5/06

  Wet spinning methods {(D01D5/0046 takes precedence)} · CPC title

• D01F9/12 Primary

  Carbon filaments; Apparatus specially adapted for the manufacture thereof · CPC title

• C01P2004/03

  obtained by SEM · CPC title