Self-organizing alignment of carbon nanotube in shape memory segmented fiber prepared by in situ polymerization and melt spinning

Shape memory polyurethane-multi-walled carbon nanotube (SMP-MWNT) fibers with different MWNT contents were prepared using in situ polymerization and melt spinning. It was found that in the shape memory polyurethane matrix, the MWNTs were preferentially aligned in the fiber axial direction. The effect of aligned MWNTs on the shape memory behavior of shape memory fibers was investigated. The shape recovery ratio and recovery force were prominently improved by the aligned MWNTs. The results suggest that the aligned MWNTs could help storing and releasing the internal elastic energy during stretching and relaxation. Besides, it was found that the self-aligned MWNTs shape memory fibers recovered the original length more quickly. This provides the possibility of fabricating smart instruments with higher sensitivity.