Carbon nanotubes are considered to be one of the strongest materials discovered by humans, with a Young’s modulus of over 1 TPa and a tensile strength of over 100 GPa (the specific strength is as high as 62.5 GPa/(g/cm3). ), more than 10 times stronger than T1000 carbon fiber. Theoretical calculations show that carbon nanotubes are currently the only material that has the potential to help us realize our dream of a space elevator.
How to maintain the excellent mechanical properties of a single carbon nanotube after assembling is the first problem that must be solved in the preparation of super strong fibers. However, the reported strength of carbon nanotube fibers is only 0.5–8.8 GPa, which is far lower than the theoretical strength of carbon nanotubes (>100 GPa). The main reason is that the carbon nanotubes that form fibers are short in length, and the units overlap each other by van der Waals force, which easily slips each other under the action of tension, and cannot fully utilize the inherent high strength of carbon nanotubes. In addition, structural defects and disordered orientations in carbon nanotubes will lead to the decrease of fiber strength. In contrast, ultra-long carbon nanotubes have lengths of centimeters or even decimeters and have perfect structures, consistent orientations, and mechanical properties close to the theoretical limit, which have great advantages in the preparation of ultra-strong fibers.
With the support of the national key R&D program “Nanotechnology”, Professor Wei Fei’s team of Tsinghua University and Professor Li Xide’s team have made a breakthrough in the field of super-strength carbon nanotube fibers. Preparation of ultralong carbon nanotube bundles for theoretical strength. By adopting the method of in-situ airflow focusing, the research team controllably prepared centimeter-scale continuous ultra-long carbon nanotube bundles with definite composition, perfect structure and parallel arrangement, ingeniously avoiding the above-mentioned limiting factors. By preparing ultralong carbon nanotube bundles containing different numbers of units, quantitatively analyzing the effects of their composition and structure on the mechanical properties of ultralong carbon nanotube bundles, a definite physical/mathematical model was established. A “synchronized relaxation” strategy is proposed to release the initial stress of carbon nanotubes in the tube bundle through nanomanipulation, so that it is in a narrow distribution range, and then the tensile strength of the carbon nanotube bundle can be increased to 80 GPa. The above is close to the tensile strength of a single carbon nanotube. The reported tensile strength of ultralong carbon nanotube bundles is superior to all other fiber materials found so far. This work reveals the bright prospect of ultra-long carbon nanotubes for the manufacture of super-strong fibers, and points out the direction and method for the development of new super-strong fibers.
As carbon nanotube suppliers, Hongwu Nanomaterial is providing several specs cnts as follows.
1.Single walled carbon nanotube,SWCNTs, D 2nm, L 1-2um, 91%;
2.Single walled carbon nanotube,SWCNTs, D 2nm, L 5-20um, 91%;
3.Multi walled carbon nanotube, MWCNTs, D 10-30nm, L 1-2um,99%;
4.Multi walled carbon nanotube, MWCNTs, D 10-30nm, L 5-20um,99%;
5.Multi walled carbon nanotube, MWCNTs, D 30-60nm, L 1-2um,99%;
6.Multi walled carbon nanotube, MWCNTs, D 30-60nm, L 5-20um,99%;
7.Multi walled carbon nanotube, MWCNTs, D 60-100nm, L 1-2um,99%;
8.Multi walled carbon nanotube, MWCNTs, D 60-100nm, L 5-20um,99%;
- functionized cnts(-COOH, -OH, -NH2, Ni plated, graphited)