“…The structural defect densities of the MWCNTs, namely the number of the defects per unit of MWCNT length were quantified by measuring the number of the structural defects in 3-5 TEM 2 For more than two decades, many researchers have focused on carbon nanotubes (CNTs) which have remarkable values for their Young's modulus, tensile strength (Peng, et al, 2008), electrical/thermal conductivity Lorents, 1995, Ebbesen, et al, 1996) and negative thermal expansion coefficient (Yoshida, 2000, Shirasu, et al, 2015, motivating their use in composites as a fibrous reinforcing agent. Recently, continuous multi-walled CNT (MWCNT) yarns and sheets, which are prepared by directly drawing MWCNTs from spinnable MWCNT arrays, have been developed (Zhang, et al, 2004(Zhang, et al, , 2005 and new processing methods utilizing MWCNT yarns and sheets have emerged as means of producing preforms and composites with higher MWCNT volume fractions (Di, et al, 2014). The Young's modulus and strength of CNTs are well known to depend critically on the structure (e.g.…”