Vibration reduction is of great importance in various engineering applications, and a material that exhibits good vibration damping along with high strength and modulus has become more and more vital. Owing to the superior mechanical property of carbon nanotube (CNT), new types of vibration damping material can be developed. This paper presents recent advancements, including our progresses, in the development of highdamping macroscopic CNT assembly materials, such as forests, gels, films, and fibers. In these assemblies, structural deformation of CNTs, zipping and unzipping at CNT connection nodes, strengthening and welding of the nodes, and sliding between CNTs or CNT bundles are playing important roles in determining the viscoelasticity, and elasticity as well. Towards the damping enhancement, strategies for micro-structure and interface design are also discussed.

The large surface area and rich functional groups of a 2D nanostructure, sulfonated graphenal polymer (SGP), provide a new strategy to assist the dispersion of carbon nanotubes (CNTs), far better than the dispersing ability of graphene oxide and sodium dodecyl benzene sulfonate. The efficient codispersion of CNTs and SGP facilitate the fabrication of composite buckypapers with wide‐range tunable fractions of CNT, SGP, and polymer, like poly(vinyl alcohol) (PVA), making it possible to search out the most optimal structure in the fraction space of the constituents. The globally strongest buckypaper is obtained at a CNT:SGP:PVA mass ratio of 7:3:10. Owing to the super hydrophilicity of SGP, and the hydrophilic characteristics of PVA as well, the composite structure can be reassembled with the aid of water, resulting in easy removal of creases and efficient cut heal/repair to broken papers. The healed papers can exhibit about 80% recovery of the tensile strength. Furthermore, just by mechanical stirring, the composite buckypaper can be redissolved in water for a totally green recycling reuse.