Effect of orientation on the modulus of SWNT films and fibers

The modulus of single wall carbon nanotube (SWNT) films and fibers, calculated using continuum mechanics and the SWNT rope elastic constants, is consistent with the experimentally measured moduli of these products. The modulus of large diameter ropes drops precipitously with orientation, while the smaller diameter rope modulus exhibits lower orientation dependence. Therefore, in addition to orientation, for the ropes composed of SWNTs with varying diameters and helicity, exfoliation also appears to be important in achieving high modulus SWNT films and fibers.