Tunable Mechanical Properties of Aligned Carbon Nanotubes Polymer Composites

One of the important members of polymer based nanocomposites, carbon nanotube aligned composites have been drawn great amount of attention and made a great contribution in material industry and academia. Nanocomposite scaffolds comprising of aligned polyvinyl alcohol (PVA) polymer and single-walled carbon nanotube (SWCNTs) nanocomposites, is emerging as a next-generation smart nanomaterial industry for use in aerospace structures due to the tunable mechanical properties with the application of stretching. In this study, we focused on the structural anisotropy in mechanical properties as a result of the controlled mechanical alignment process. Here, we show that the first forming hydrogels or aerogels of individually dispersed single wall carbon nanotubes and then partial backfilling with polymer. The SWCNTs in composites aligned in a controlled manner with the help of DMA technique and re-backfilled aligned composites with the polymer to remove voids. The Raman spectroscopy has confirmed the preferential orientation of alignment of SWCNTs, due to the application of stretching. Further, the nanotube networks suppress the polymer glass transition, increase the endothermic peak temperature and extend the mechanical integrity of polymer. Both the nanotubes and polymer remain thermally stable well above their decomposition temperature. The controlling internal orientation order of nanotubes in composite scaffolds can bring a tunable range of thermal, electrical and mechanical properties, which would combine with the creating highly structural anisotropic properties. This might be useful for designing new applications in the smart nanomaterial industry such as aerospace, defense and healthcare.