Orientation and thermal properties of carbon nanotube/polyacrylonitrile nascent composite fibers

The carbon nanotube (CNT)/polyacrylonitrile (PAN) nascent composite fibers were prepared by wet spinning method. The polarized technique was used to characterize the nitrile orientation and the CNTs orientation in the CNT/PAN nascent composite fibers, and the crystal orientation was also characterized by the azimuthal scan of X-ray diffraction. The results showed that the CNTs had high orientation in the nascent composite fibers after wet spinning, and the nitrile groups of the nascent composite fibers had higher orientation than that of the PAN nascent fibers owing to the interfacial interaction between CNTs and PAN macromolecular chains. Moreover, the CNT/PAN nascent composite fibers had higher parameters of crystal structure and excellent mechanical properties than the PAN nascent fibers. Meanwhile, the addition of CNTs into PAN matrix decreased the intensity of evolved heat in nitrogen atmosphere and made microstructure more compactness than the control PAN nascent fibers.