Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Mechanochemical strengthening of a synthetic polymer in response to typically destructive shear forces

Nature Chemistry volume 5, pages 757–761 (2013)Cite this article

Subjects

Abstract

High shear stresses are known to trigger destructive bond-scission reactions in polymers. Recent work has shown that the same shear forces can be used to accelerate non-destructive reactions in mechanophores along polymer backbones, and it is demonstrated here that such mechanochemical reactions can be used to strengthen a polymer subjected to otherwise destructive shear forces. Polybutadiene was functionalized with dibromocyclopropane mechanophores, whose mechanical activation generates allylic bromides that are crosslinked in situ by nucleophilic substitution reactions with carboxylates. The crosslinking is activated efficiently by shear forces both in solvated systems and in bulk materials, and the resulting covalent polymer networks possess moduli that are orders-of-magnitude greater than those of the unactivated polymers. These molecular-level responses and their impact on polymer properties have implications for the design of materials that, like biological materials, actively remodel locally as a function of their physical environment.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: The mechanochemical self-strengthening concept.
Figure 2: Shear-induced mechanochemical crosslinking in solution and the bulk.
Figure 3: Chemistry and response of a single-component ARM system.

Similar content being viewed by others

References

  1. Odell, J. A. & Keller, A. Flow-induced chain fracture of isolated linear macromolecules in solution. J. Polym. Sci. B 24, 1889–1916 (1986).

    Article  CAS  Google Scholar 

  2. Kudish, I. I., Airapetyan, R. G. & Covitch, M. J. Modeling of kinetics of stress-induced degradation of polymer additives in lubricants and viscosity loss. Tribol. Trans. 46, 1–10 (2003).

    Article  CAS  Google Scholar 

  3. Zhurkov, S. N. & Korsukov, V. E. Atomic mechanism of fracture of solid polymers. J. Polym. Sci. B 12, 385–398 (1974).

    CAS  Google Scholar 

  4. Keckes, J. et al. Cell-wall recovery after irreversible deformation of wood. Nature Mater. 2, 810–814 (2003).

    Article  CAS  Google Scholar 

  5. Watson, G. M. & Mire, P. Reorganization of actin during repair of hair bundle mechanoreceptors. J. Neurocytol. 30, 895–906 (2001).

    Article  CAS  Google Scholar 

  6. Caruso, M. M. et al. Mechanically-induced chemical changes in polymeric materials. Chem. Rev. 109, 5755–5798 (2009).

    Article  CAS  Google Scholar 

  7. Black, A. L., Lenhardt, J. M. & Craig, S. L. From molecular mechanochemistry to stress-responsive materials. J. Mater. Chem. 21, 1655–1663 (2011).

    Article  CAS  Google Scholar 

  8. Hickenboth, C. R. et al. Biasing reaction pathways with mechanical force. Nature 446, 423–427 (2007).

    Article  CAS  Google Scholar 

  9. Lenhardt, J. M. et al. Trapping a diradical transition state by mechanochemical polymer extension. Science 329, 1057–1060 (2010).

    Article  CAS  Google Scholar 

  10. Wu, D., Lenhardt, J. M., Black, A. L., Akhremitchev, B. B. & Craig, S. L. Molecular stress relief through a force-induced irreversible extension in polymer contour length. J. Am. Chem. Soc. 132, 15936–15938 (2010).

    Article  CAS  Google Scholar 

  11. Park, I. & Sheiko, S. S. Molecular tensile testing machines: breaking a specific covalent bond by adsorption-induced tension in brushlike macromolecules. Macromolecules 42, 1805–1807 (2009).

    Article  CAS  Google Scholar 

  12. Wiita, A. P., Ainavarapu, S. R. K., Huang, H. H. & Fernandez, J. M. Force-dependent chemical kinetics of disulfide bond reduction observed with single-molecule techniques. Proc. Natl Acad. Sci. USA 103, 7222–7227 (2006).

    Article  CAS  Google Scholar 

  13. Brantley, J. N., Wiggins, K. M. & Bielawski, C. W. Unclicking the click: mechanically facilitated 1,3-dipolar cycloreversions. Science 333, 1606–1609 (2011).

    Article  CAS  Google Scholar 

  14. Black, A. L., Orlicki, J. A. & Craig, S. L. Mechanochemically triggered bond formation in solid-state polymers. J. Mater. Chem. 21, 8460–8465 (2011).

    Article  CAS  Google Scholar 

  15. Berkowski, K. L., Potisek, S. L., Hickenboth, C. R. & Moore, J. S. Ultrasound-induced site-specific cleavage of azo-functionalized poly(ethylene glycol). Macromolecules 38, 8975–8978 (2005).

    Article  CAS  Google Scholar 

  16. Karthikeyan, S., Potisek, S. L., Piermattei, A. & Sijbesma, R. P. Highly efficient mechanochemical scission of silver–carbene coordination polymers. J. Am. Chem. Soc. 130, 14968–14969 (2008).

    Article  CAS  Google Scholar 

  17. Kryger, M. J. et al. Masked cyanoacrylates unveiled by mechanical force. J. Am. Chem. Soc. 132, 4558–4559 (2010).

    Article  CAS  Google Scholar 

  18. Paulusse, J. M. J. & Sijbesma, R. P. Reversible mechanochemistry of a Pd(II) coordination polymer. Angew. Chem. Int. Ed. 43, 4460–462 (2004).

    Article  CAS  Google Scholar 

  19. Yang, Q-Z. et al. A molecular force probe. Nature Nanotech. 4, 302–306 (2009).

    Article  CAS  Google Scholar 

  20. Klukovich, H. M. et al. Tension trapping of carbonyl ylides facilitated by a change in polymer backbone. J. Am. Chem. Soc. 134, 9577–9580 (2012).

    Article  CAS  Google Scholar 

  21. Klukovich, H. M., Kouznetsova, T. B., Kean, Z. S., Lenhardt, J. M. & Craig, S. L. A backbone lever-arm effect enhances polymer mechanochemistry. Nature Chem. 5, 110–114 (2013).

    Article  CAS  Google Scholar 

  22. Davis, D. A. et al. Force-induced activation of covalent bonds in mechanoresponsive polymeric materials. Nature 459, 68–71 (2009).

    Article  CAS  Google Scholar 

  23. Crenshaw, B. R. et al. Deformation induced color changes in mechanochromic polyethylene blends. Macromolecules 40, 2400–2408 (2007).

    Article  CAS  Google Scholar 

  24. Chen, Y. et al. Mechanically induced chemiluminescence from polymers incorporating a 1,2-dioxetane unit in the main chain. Nature Chem. 4, 559–562 (2012).

    Article  CAS  Google Scholar 

  25. Kean, Z. S. & Craig, S. L. Mechanochemical remodeling of synthetic polymers. Polymer 53, 1035–1048 (2012).

    Article  CAS  Google Scholar 

  26. Oliver, W. C. & Pharr, G. M. An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564–1583 (1992).

    Article  CAS  Google Scholar 

  27. Paulusse, J. M. J. & Sijbesma, R. P. Ultrasound in polymer chemistry: revival of an established technique. J. Polym. Sci. Polym. Chem. 44, 5445–5453 (2006).

    Article  CAS  Google Scholar 

  28. May, P. A. & Moore, J. S. Polymer mechanochemistry: techniques to generate molecular force via elongational flows. Chem. Soc. Rev. http://dx.doi.org/10.1039/c2cs35463b (2013).

  29. Basedow, A. M. & Ebert, K. H. in Advances in Polymer Science Vol. 22 (eds Cantow, H-J. et al.) 83–148 (Springer, 1977).

    Google Scholar 

  30. Nguyen, T. Q., Liang, Q. Z. & Kausch, H. H. Kinetics of ultrasonic and transient elongational flow degradation: a comparative study. Polymer 38, 3783–3793 (1997).

    Article  CAS  Google Scholar 

  31. Schosseler, F., Benoit, H., Grubisic-Gallot, Z., Strazielle, C. & Leibler, L. Gelation process by size-exclusion chromatography coupled with light scattering. Macromolecules 22, 400–410 (1989).

    Article  CAS  Google Scholar 

  32. Francis, R. S., Patterson, G. D. & Kim, S. H. Liquid-like structure of polymer solutions near the overlap concentration. J. Polym. Sci. Polym. Phys. 44, 703–710 (2005).

    Article  Google Scholar 

  33. Naota, T. & Koori, H. Molecules that assemble by sound: an application to the instant gelation of stable organic fluids J. Am. Chem. Soc. 127, 9324–9325 (2005).

    Article  CAS  Google Scholar 

  34. Carnall, J. M. A. et al. Mechanosensitive self-replication driven by self-organization. Science 327, 1502–1506 (2010).

    Article  CAS  Google Scholar 

  35. Carey, B. J., Patra, P. K., Ci, L., Silva, G. G. & Ajayan, P. M. Observation of dynamic strain hardening in polymer nanocomposites. ACS Nano 5, 2715–2722 (2011).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This material is based on work supported by the US Army Research Laboratory and the Army Research Office under Grant W911NF-07-1-0409 and the National Science Foundation (DMR-1122483). A.L.B.R. was supported by a Department of Defense Science, Mathematics and Research for Transformation Fellowship and Z.S.K. by a National Institutes of Health NIGMS Biotechnology Predoctoral Training Grant (T32GM8555).

Author information

Authors and Affiliations

  1. Department of Chemistry, Duke University, Durham, 27708, North Carolina, USA

    Ashley L. Black Ramirez, Zachary S. Kean, Sarah M. Elsakr & Stephen L. Craig

  2. Weapons & Materials Research Directorate, Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, 21005, Maryland, USA

    Joshua A. Orlicki

  3. Department of Textile Engineering, Chemistry and Science, North Carolina State University, Raleigh, 27695, North Carolina, USA

    Mangesh Champhekar & Wendy E. Krause

Authors
  1. Ashley L. Black Ramirez
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Zachary S. Kean
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Joshua A. Orlicki
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Mangesh Champhekar
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Sarah M. Elsakr
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Wendy E. Krause
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Stephen L. Craig
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

A.L.B.R. and S.L.C. conceived and designed the experiments. A.L.B.R. and Z.S.K. performed the synthesis, J.A.O. contributed extrusion equipment and analysed that data with A.L.B.R. A.L.B.R. and S.M.E. performed the shear experiments. W.E.K. contributed the nanoindentation tools and M.C. performed the nanoindentation experiments and analysed that data. A.L.B.R., Z.S.K. and S.L C. analysed the data and co-wrote the paper.

Corresponding author

Correspondence to Stephen L. Craig.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary information

Supplementary information (PDF 4280 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Ramirez, A., Kean, Z., Orlicki, J. et al. Mechanochemical strengthening of a synthetic polymer in response to typically destructive shear forces. Nature Chem 5, 757–761 (2013). https://doi.org/10.1038/nchem.1720

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nchem.1720

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing