In a paper by Wallace,it shown that volume resistivity of graphite is the range 4 x 10-5 ?mto 6 x10-5 ?m (Wallace, 1947). Since graphitehas some similarity with MWCNT in term of numerous layer, the result can becompared with study conducted by Stetter et.
al, which has intershell spacingbetween 0.39 to 0.34 nm. The result obtained at room temperature is 0.068 ?m,with diameter of 33 nm (Stetter et al.
, 2010). While a studyconducted by Bourbon et. al, found that conductance of MWCNT is independent totemperature with volume resistivity in the range of 0.34 ?m-1.8 ?m (Bourlon, Miko, Forró, Glattli, and Bachtold, 2004).
Contrary,study by Stetter found that, resistivity increases as temperature decrease. Inagreement with this findings is study by Ebbesen which shows sudden increasesin resistance as temperature decrease. (Ebbesen, T.
W., Lezec H. J., Hiura H., Bennett J. W.
,Ghaemi H. F, 1996). The statedfindings is based on measurement on individual carbon nanotube. This resultindicate that, generally, conductivity is decrease at lower than roomtemperature and increase at higher temperature. Fromvarious experimental results, generally, CNT fiber synthesized from directspinning process has higher electrical conductivity than CNT fiber from wetspinning but lower conductivity of CNT fiber from array. (Jingdong, 2015). Contrary, CNTyarn which a part CNT fiber reported that to have higher conductivity in directspinning process compared to CNT yarn spun from array and CNT yarn spun fromwet spinning, which has conductivity of 5 x 105 S/m(Zhong et al., 2010) (1.
7-4.1) x 104S/m (Zhang et al., 2007), (1-2) x 103S/m(Vigolo, Vigolo, Pe, & Coulon, 2013) respectively. Thiscomparison shows that, direct spinning process provides better result inelectrical conductivity owing to conductivity of CNT bundles during synthesizeditself.
