Topics in Catalysis

, Volume 61, Issue 7–8, pp 704–709 | Cite as

Mechanism and Catalysis of Oxidative Degradation of Fiber-Reinforced Epoxy Composites

  • Carlos A. Navarro
  • Elyse A. Kedzie
  • Yijia Ma
  • Katelyn H. Michael
  • Steven R. Nutt
  • Travis J. Williams
Original Paper


Carbon fiber-reinforced polymer (CFRP) materials are widely used in aerospace and recreational equipment, but there is no efficient procedure for their end-of-life recycling. Ongoing work in the chemistry and engineering communities emphasizes recovering carbon fibers from such waste streams by dissolving or destroying the polymer binding. By contrast, our goal is to depolymerize amine-cured epoxy CFRP composites catalytically, thus enabling not only isolation of high-value carbon fibers, but simultaneously opening an approach to recovery of small molecule monomers that can be used to regenerate precursors to new composite resin. To do so will require understanding of the molecular mechanism(s) of such degradation sequences. Prior work has shown the utility of hydrogen peroxide as a reagent to affect epoxy matrix decomposition. Herein we describe the chemical transformations involved in that sequence: the reaction proceeds by oxygen atom transfer to the polymer’s linking aniline group, forming an N-oxide intermediate. The polymer is then cleaved by an elimination and hydrolysis sequence. We find that elimination is the slower step. Scandium trichloride is an efficient catalyst for this step, reducing reaction time in homogeneous model systems and neat cured matrix blocks. The conditions can be applied to composed composite materials, from which pristine carbon fibers can be recovered.


Recycling Epoxy Composites Carbon fiber Depolymerize Catalysis 



Financial support from the USC Zumberge fund, the M.C. Gill Composites Center at USC, the National Science Foundation (CHE-1566167), and George Olah’s Hydrocarbon Research Foundation are gratefully acknowledged. We thank the NSF (DBI-0821671, CHE-0840366) and the NIH (S10 RR25432) for NMR spectrometers.

Supplementary material

11244_2018_917_MOESM1_ESM.docx (6.1 mb)
Supplementary material 1 (DOCX 6227 KB)


  1. 1.
    Xu P, Li J, Ding J (2013) Composites Sci Technol 82:54–59CrossRefGoogle Scholar
  2. 2.
    Das M, Varughese S (2016) ACS Sustain Chem Eng 4:2080–2087CrossRefGoogle Scholar
  3. 3.
    Campbell FC (2006) Manufacturing technology for aerospace structural materials. Elsevier, LondonGoogle Scholar
  4. 4.
    Asmatulu E, Twomey J, Overcash M (2013) J Compos Mater 48:593–608CrossRefGoogle Scholar
  5. 5.
    European Parliament, Council of the European Union. (2000) Directive 2000/53/EC of the European Parliament and of the Council; OJ L 269:L0053; 2013Google Scholar
  6. 6.
    Oliveux G, Dandy LO, Leeke GA (2015) Prog Mater Sci 72:61–99CrossRefGoogle Scholar
  7. 7.
    Piment S, Pinho ST (2011) Waste Manag 31:378–392CrossRefGoogle Scholar
  8. 8.
    Shibata K, Nakagawa M (2014) CFRP Recycling technology using depolymerization under ordinary pressure. Hitachi Chemical Technical Report No. 56Google Scholar
  9. 9.
    Maekawa K, Shibata K, Kuriya H, Nakagawa M (2011) Proceedings of 60th the Society of Polymer Science Japan Annual Meeting, p 6Google Scholar
  10. 10.
    Gella C, Ferrer È, Alibés R, Busqué F, de March P, Figueredo M, Font J (2009) J Org Chem 74:6365–6367CrossRefGoogle Scholar
  11. 11.
    Murray RW, Iyanar K (1996) J Org Chem 61:8099–8102CrossRefGoogle Scholar
  12. 12.
    Aurich HG, Franzke M, Kesselheim HP (1992) Tetrahedron 48:663–668CrossRefGoogle Scholar
  13. 13.
    Hudson A, Betz D, Kühn FE, Jiménez-Alemán GH, Boland W (2013) Methyltrioxorhenium. In Fuchs PL (ed) Encyclopedia of reagents for organic synthesis. Wiley, New YorkGoogle Scholar
  14. 14.
    Wang Y, Cui X, Ge H, Yang Y, Wang Y, Zhang C, Li J, Deng T, Qin Z, Hou X (2015) ACS Sustain Chem Eng 3:3332–3337CrossRefGoogle Scholar
  15. 15.
    Liu T, Zhang M, Guo X, Liu C, Liu T, Xin J, Zhang J (2017) Polym Degrad Stab 139:20–27CrossRefGoogle Scholar
  16. 16.
    Pimenta S, Pinho ST (2011) Waste Manag 31:378–392CrossRefGoogle Scholar
  17. 17.
    Witik RA, Gaille F, Teuscher R, Ringwald H, Michaud V, Månson J-AE (2012) J Clean Prod 29–30:91–102CrossRefGoogle Scholar
  18. 18.
    Witik RA, Payet J, Michaud V, Ludwig C, Månson J-AE (2011) Composites Part A 42:1694–1709CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Loker Hydrocarbon Research Institute and Department of ChemistryUniversity of Southern CaliforniaLos AngelesUSA
  2. 2.M.C. Gill Composites Center and Mork Family Department of Chemical Engineering and Materials ScienceUniversity of Southern CaliforniaLos AngelesUSA

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