Structural Chemistry

, Volume 30, Issue 1, pp 341–349 | Cite as

Increasing mechanical resilience and enhanced electrical conductivity through the incorporation of CNF reinforcing additives in PA6 nanocomposites

  • J. Paige BuchananEmail author
  • Erin R. Reed-Gore
  • Jennifer A. Jefcoat
  • Robert D. Moser
  • Kyle L. Klaus
  • Hannah R. Peel
  • Randy K. Buchanan
  • Eftihia Barnes
  • Erik M. Alberts
  • Manoj K. ShuklaEmail author
Original Research


In pursuit of strong, tough, and functional advanced composite materials, a series of polymer nanocomposite blends were prepared from the engineering thermoplastic polyamide 6 (PA6) and increasing admixtures of carbon nanofibers (CNF) up to 8 wt%. The combination of high sheer mixing and solvent processing techniques employed produced free-standing films of 40–60-μm thickness, which were characterized for mechanical performance, dispersion, thermal behavior, and electrical conductivity. The combination of XRD, FTIR, Raman, and SEM analysis supported a dominant α-phase PA6 and good dispersion of the CNF. CNF:PA6 composite films yield an impressive ~ 500% elongation at break for 2 wt% CNF, with more modest increases in tensile strength and elastic modulus over the unmodified PA6. DSC analysis suggests strong interfacial forces between additive and polymer, with a nucleating effect on the formation of crystallites. Increasing CNF loading leads to enhanced thermal stability, and a significant increase in electrical conductivity was observed at low loadings of CNF. These materials show great promise for use in advanced composites applications.


Thermoplastic Polyamide 6 Carbon nanofiber Mechanical properties Electrical conductivity 



The use of trade, product, or firm names in this report is for descriptive purposes only and does not imply endorsement by the US Government. The tests described and the resulting data presented herein, unless otherwise noted, are based upon work supported by the US Army Basic Research Program under PE 61102, Project T22, Task 01 “Military Engineering Basic Research.” Permission was granted by the Director, GSL to publish this information. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

11224_2018_1236_MOESM1_ESM.docx (505 kb)
ESM 1 (DOCX 505 kb)


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Copyright information

© This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2018

Authors and Affiliations

  1. 1.Geotechnical and Structures Laboratory, US Army Corps of EngineersEngineer Research and Development CenterVicksburgUSA
  2. 2.Environmental Laboratory, US Army Corps of EngineersEngineer Research and Development CenterVicksburgUSA
  3. 3.Information Technology Laboratory, US Army Corps of EngineersEngineer Research and Development CenterVicksburgUSA
  4. 4.HX5, LLCVicksburgUSA

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