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Multi-walled nanotubes (MWNTs) consist of multiple rolled layers (concentric tubes) of graphene. There are two models that can be used to describe the structures of multi-walled nanotubes.
CNT045 (OTTO) Multi-walled carbon nanotubes, 99% (OD: 60-80 nm, Length: 1-2 um) - used as composite fibers in polymers to improve the mechanical, thermal and electrical properties of the bulk product.