Effect of Templating Graphitization of Functionalized SWNTs on Mechanical Properties of Hot-drawn Carbon Nanofibers Conference Paper uri icon

abstract

  • © 2018, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved. The Graphitization process, formation of low defect-density graphitic domains, in nanomaterials such as carbon nanofibers (CNFs) that are obtained by carbonizing polymer precursors can be promoted by including highly graphitic nanomaterials such as CNTs in polymeric precursors. The formation of graphitic domains can in principle lead to significant improvements in mechanical strength and modulus of CNFs by introducing stable sp2 C-C bonds into the structure. In this work, templating effect of CNTs in CNFs and the contribution of that to mechanical properties of CNFs is studied. The precursors were fabricated via electrospinning of a solution of polyacrylonitrile (PAN) and functionalized single walled CNTs (f-SWNTs). To better orient the CNTs with the axis of the fiber and also to enhance the packing of polymer chains of the precursor around CNTs, the as-electrospun fibers were subjected to thermo-mechanical processing. In this work, low concentration of f-SWNTs (0.5 wt.%) was used to achieve uniform dispersion of tubes. The microstructure of CNF was characterized by different methods, such as, Raman spectroscopy and 2D wide-angle X-ray diffraction. The Micro-Electro-Mechanical System (MEMS) based single nanofiber mechanical testing results show the strong relationship between the modulus, strength improvement and the hot-drawing process. The existence and evolution of the highly order phase around the CNTs and its influence on the overall mechanical property of CNF are also discussed.

author list (cited authors)

  • Cai, J., & Naraghi, M.

citation count

  • 1

publication date

  • January 2018