Effect of Strain Hardening on the Elastic Properties and Normalized Velocity of Hybrid UHMWPE-Nylon 6-SWCNT Nanocomposites Fiber

<div class="line" id="line-16"> Hybrid ultrahigh molecular weight polyethylene&ndash;nylon 6&ndash;single-wall carbon nanotube fibers were processed using solution spinning method. Elastic properties and normalized velocity ( <img src="file:///C:/Users/LIBCRS~1/AppData/Local/Temp/msohtmlclip1/01/clip_image001.gif"/> ) of the hybrid fibers were measured before and after strain hardening through repeated loading&ndash;unloading cycles. Phenomenal improvement in the properties was found: strength, modulus, and normalizing velocity increased by almost one order of magnitude after strain hardening. Neat and reinforced filaments were characterized through differential scanning calorimetry, Raman spectroscopy, and scanning electron microscope before and after strain hardening. It has been revealed that nylon 6 contributed to the deformation ability of the composite fiber, while carbon nanotubes contributed to the sharing of load as they aligned during extrusion and strain hardening processes. Important morphological features determining the fiber properties were the change in crystallinity and rate of crystallization, formation of microdroplets, interfacial sliding, polymer coating of nanotubes, alignment of polymer fibrils and nanotubes.</div>