In situ Polymerization of Polyamide 6/Carbon Nanotubes Nanocomposites and Their Melt Spinning Fibers

Carbon nanotubes (CNTs)/polyamide-6 (PA6) nanocomposites with different CNTs loadings have been prepared by in situ polymerization approach. Then the blends were extruded into fibers using melt spinning technology to prepare as-spun and drawn fibers. Scanning electron microscopy observation on the fracture surfaces of the composite’s fiber shows not only a uniform dispersion of CNTs but also a strong interfacial adhesion with the matrix. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results show that CNTs act as strong heterogeneous nucleating agents for PA6 crystals. The breaking strength of drawn composite fibers, with incorporating less than 4 wt % CNTs, is slightly higher than that of pure PA fibers prepared at the same draw ratio. The PA6/CNTs composite fibers reveal a high increase in breaking strength as the draw ratio increased. Due to the electric conductivity of CNTs, electrical resistivity of the PA6/CNTs composite fibers is reduced.