NASA’s Langley Research Center has developed a method to consolidate carbon nanotube yarns and woven sheets and graphene sheets via the dehydration of sucrose. The resulting materials are lightweight and high strength. Sucrose is relatively inexpensive and readily available; therefore the process is cost-effective.
Various aerospace and terrestrial applications require lightweight materials with very high mechanical properties. Carbon nanotubes and graphene sheets have been found to be such materials. In addition, they have been found to have excellent electrical and thermal transport properties. However, retaining the excellent nanoscale properties — particularly mechanical and thermal transport properties — in bulk materials has proven to be challenging. In order for the nanotubes to be used in applications, they must be spun into yarn(s), sheet(s), and other macroscopic forms introducing relatively weak tube-to-tube and inter-bundle bonds. Also, the nano tubes tend to be entangled, and they therefore do not all contribute in load bearing. Weak coupling at tube and bundle interfaces also leads to mechanical and thermal transport that are much lower than would be expected from the nanoscale carbon nano tube or graphene properties.
This invention is for consolidated carbon nanotube or graphene yarns and woven sheets via the formation of a carbon binder formed from the dehydration of sucrose. The resulting materials have greater than a 30% increase in tensile properties compared to the starting materials. They are lightweight and possess a high specific modulus and/or strength on the macro-scale. In addition, the dielectric and electrical properties of the yarns and sheets can be tailored. Sucrose is relatively inexpensive and readily available, leading to a cost-effective route for achieving bulk nanotube/graphene-based, multifunctional material formats.
Potential applications include structural materials for aerospace vehicles, materials for lightweight but mechanically robust consumer devices, and materials for space habitats.