sentence: Carbon nanotubes are very tough and hard to break, but still relatively light.
sentences_before: This animation of a spinning carbon nanotube shows its 3D structure. Some allotropes of carbon. A 'carbon nanotube' is an allotrope of carbon that is shaped like a tube of carbon atoms.
sentences_after: Because of their high strength, carbon nanotubes may one day be used for bulletproof armor and other uses needing hard, lightweight materials. Some carbon nanotubes also let electricity through them. Certain nanotubes may be up to 1,000 times as good conductors as metals like copper and silver.
concept_name: carbon nanotube
headings: Carbon nanotube
categories: Carbon