Enhancement of strength and stiffness of Nylon 6 filaments through carbon nanotubes reinforcement

We report a method to fabricate carbon nanotube reinforced Nylon filaments through an extrusion process. In this process, Nylon 6 and multiwalled carbon nanotubes (MWCNT) are first dry mixed and then extruded in the form of continuous filaments by a single screw extrusion method. Thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) studies have indicated that there is a moderate increase in T-g without a discernible shift in the melting endotherm. Tensile tests on single filaments have demonstrated that Young's modulus and strength of the nanophased filaments have increased by 220% and 164%, respectively with the addition of only 1 wt. % MWCNTs. SEM studies and micromechanics based calculations have shown that the alignment of MWCNTs in the filaments, and high interfacial shear strength between the matrix and the nanotube reinforcement was responsible for such a dramatic improvement in properties. (c) 2006 American Institute of Physics.