Dette er fra et lengere utdrag fra et universitet i Mansoria som jeg hadde tatt vare på, egentlig er dette mye mer komplisert da det finnes flere underarter av disse graphen stoffene. Man må være svært godt skolert i emnet for å skjønne alle detaljene. Som sagt så sier de ingenting om produksjonsmetodene er fra pyrolyse eller andre metoder

CNTs are divided into single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) based on the number of graphene sheets. SWCNTs have a diameter range of 0.5 to 12 nm but the smallest diameter of SWCNTs is 0.4 nm with different tube lengths starting from few micrometers depending on manufacturing and treatment techniques. MWCNTs consist of multi rolled layers of graphene inserted one into the other and the number of graphene walls may reach more than 25 walls with spacing of 0.34 nm. The outside diameter of MWCNTs ranges from 1 nm to 50 nm while the inside diameter is several nanometers. As a material modification, MWCNTs is better than SWCNTs as it is stiffer, easier, and cheaper to produce on a large scale.