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Olefin metathesis-based chemically recyclable polymers enabled by fused-ring monomers

Abstract

A promising solution to address the challenges in plastics sustainability is to replace current polymers with chemically recyclable ones that can depolymerize into their constituent monomers to enable the circular use of materials. Despite some progress, few depolymerizable polymers exhibit the desirable thermal stability and strong mechanical properties of traditional polymers. Here we report a series of chemically recyclable polymers that show excellent thermal stability (decomposition temperature >370 °C) and tunable mechanical properties. The polymers are formed through ring-opening metathesis polymerization of cyclooctene with a trans-cyclobutane installed at the 5 and 6 positions. The additional ring converts the non-depolymerizable polycyclooctene into a depolymerizable polymer by reducing the ring strain energy in the monomer (from 8.2 kcal mol–1 in unsubstituted cyclooctene to 4.9 kcal mol–1 in the fused ring). The fused-ring monomer enables a broad scope of functionalities to be incorporated, providing access to chemically recyclable elastomers and plastics that show promise as next-generation sustainable materials.

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Fig. 1: Identifying the appropriate ring that lowers the RSE for cyclooctene to enable depolymerization of the corresponding polymer.
Fig. 2: Synthesis and characterization of the tCBCO monomers and polymers.
Fig. 3: Depolymerization studies of tCBCO polymers.
Fig. 4: Newman projections along the C5–C6 bond for 1,9-dienes and cyclooctenes.
Fig. 5: Mechanical properties of tCBCO polymers.

Data availability

Crystallographic data for the structures in this Article have been deposited at the Cambridge Crystallographic Data Centre (CCDC) under deposition nos 2032007 (2), 2032008 (6) and 2032009 (10). Copies of data can be obtained free of charge from www.ccdc.cam.ac.uk/structures/. All other data supporting the findings of this study are available within the Article and its Supplementary Information. Source data are provided with this paper.

References

  1. 1.

    Rochman, C. M. et al. Classify plastic waste as hazardous. Nature 494, 169–171 (2013).

    CAS  PubMed  Google Scholar 

  2. 2.

    The New Plastics Economy: Rethinking the Future of Plastics and Catalysing Action (Ellen MacArthur Foundation, 2017).

  3. 3.

    Haider, T. P., Völker, C., Kramm, J., Landfester, K. & Wurm, F. R. Plastics of the future? The impact of biodegradable polymers on the environment and on society. Angew. Chem. Int. Ed. 58, 50–62 (2019).

    CAS  Google Scholar 

  4. 4.

    Ignatyev, I. A., Thielemans, W. & Vander Beke, B. Recycling of polymers: a review. ChemSusChem 7, 1579–1593 (2014).

    CAS  PubMed  Google Scholar 

  5. 5.

    Tang, X. & Chen, E. Y. X. Toward infinitely recyclable plastics derived from renewable cyclic esters. Chem 5, 284–312 (2019).

    CAS  Google Scholar 

  6. 6.

    Coates, G. W. & Getzler, Y. D. Y. L. Chemical recycling to monomer for an ideal, circular polymer economy. Nat. Rev. Mater. 5, 501–516 (2020).

    CAS  Google Scholar 

  7. 7.

    Snow, R. D. & Frey, F. E. The reaction of sulfur dioxide with olefins: the ceiling temperature phenomenon. J. Am. Chem. Soc. 65, 2417–2418 (1943).

    CAS  Google Scholar 

  8. 8.

    Dainton, F. S. & Ivin, K. J. Reversibility of the propagation reaction in polymerization processes and its manifestation in the phenomenon of a ‘ceiling temperature’. Nature 162, 705–707 (1948).

    CAS  Google Scholar 

  9. 9.

    McCormick, H. W. Ceiling temperature of α-methylstyrene. J. Polym. Sci. 25, 488–490 (1957).

    CAS  Google Scholar 

  10. 10.

    North, A. M. & Richardson, D. Entropy of stereoregularity in aldehyde polymerization. Polymer 6, 333–338 (1965).

    CAS  Google Scholar 

  11. 11.

    Park, C. W. et al. Thermally triggered degradation of transient electronic devices. Adv. Mater. 27, 3783–3788 (2015).

    CAS  PubMed  Google Scholar 

  12. 12.

    Feinberg, A. M. et al. Cyclic poly(phthalaldehyde): thermoforming a bulk transient material. ACS Macro Lett. 7, 47–52 (2018).

    CAS  Google Scholar 

  13. 13.

    Tran, H. et al. Stretchable and fully degradable semiconductors for transient electronics. ACS Cent. Sci. 5, 1884–1891 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  14. 14.

    Zhu, J.-B., Watson, E. M., Tang, J. & Chen, E. Y. X. A synthetic polymer system with repeatable chemical recyclability. Science 360, 398–403 (2018).

    CAS  PubMed  Google Scholar 

  15. 15.

    Grubbs, R. H. Olefin metathesis. Tetrahedron 60, 7117–7140 (2004).

    CAS  Google Scholar 

  16. 16.

    Grubbs, R. H. & Khosravi, E. Handbook of Metathesis: Polymer Synthesis 2nd edn, Vol. 3 (Wiley, 2015).

  17. 17.

    Monfette, S. & Fogg, D. E. Equilibrium ring-closing metathesis. Chem. Rev. 109, 3783–3816 (2009).

    CAS  PubMed  Google Scholar 

  18. 18.

    Neary, W. J. & Kennemur, J. G. Polypentenamer renaissance: challenges and opportunities. ACS Macro Lett. 8, 46–56 (2019).

    CAS  Google Scholar 

  19. 19.

    Myers, S. B. & Register, R. A. Synthesis of narrow-distribution polycyclopentene using a ruthenium ring-opening metathesis initiator. Polymer 49, 877–882 (2008).

    CAS  Google Scholar 

  20. 20.

    Neary, W. J. & Kennemur, J. G. Variable temperature ROMP: leveraging low ring strain thermodynamics to achieve well-defined polypentenamers. Macromolecules 50, 4935–4941 (2017).

    CAS  Google Scholar 

  21. 21.

    Schleyer, P. v. R., Williams, J. E. & Blanchard, K. R. Evaluation of strain in hydrocarbons. The strain in adamantane and its origin. J. Am. Chem. Soc. 92, 2377–2386 (1970).

    CAS  Google Scholar 

  22. 22.

    Hejl, A., Scherman, O. A. & Grubbs, R. H. Ring-opening metathesis polymerization of functionalized low-strain monomers with ruthenium-based catalysts. Macromolecules 38, 7214–7218 (2005).

    CAS  Google Scholar 

  23. 23.

    Martinez, H., Ren, N., Matta, M. E. & Hillmyer, M. A. Ring-opening metathesis polymerization of 8-membered cyclic olefins. Polym. Chem. 5, 3507–3532 (2014).

    CAS  Google Scholar 

  24. 24.

    Walker, R., Conrad, R. M. & Grubbs, R. H. The living ROMP of trans-cyclooctene. Macromolecules 42, 599–605 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  25. 25.

    You, W., Padgett, E., MacMillan, S. N., Muller, D. A. & Coates, G. W. Highly conductive and chemically stable alkaline anion exchange membranes via ROMP of trans-cyclooctene derivatives. Proc. Natl Acad. Sci. USA 116, 9729–9734 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  26. 26.

    You, W., Hugar, K. M. & Coates, G. W. Synthesis of alkaline anion exchange membranes with chemically stable imidazolium cations: unexpected cross-linked macrocycles from ring-fused ROMP monomers. Macromolecules 51, 3212–3218 (2018).

    CAS  Google Scholar 

  27. 27.

    Scherman, O. A., Walker, R. & Grubbs, R. H. Synthesis and characterization of stereoregular ethylene-vinyl alcohol copolymers made by ring-opening metathesis polymerization. Macromolecules 38, 9009–9014 (2005).

    CAS  Google Scholar 

  28. 28.

    Hsu, T.-G. et al. A polymer with “locked” degradability: superior backbone stability and accessible degradability enabled by mechanophore installation. J. Am. Chem. Soc. 142, 2100–2104 (2020).

    CAS  PubMed  Google Scholar 

  29. 29.

    Asaoka, S., Horiguchi, H., Wada, T. & Inoue, Y. Enantiodifferentiating photocyclodimerization of cyclohexene sensitized by chiral benzenecarboxylates. J. Chem. Soc. Perkin Trans. 2, 737–747 (2000).

    Google Scholar 

  30. 30.

    Maeda, H. et al. Synthesis and photochemical properties of stilbenophanes tethered by silyl chains. Control of (2π + 2π) photocycloaddition, cis−trans photoisomerization, and photocyclization. J. Org. Chem. 70, 9693–9701 (2005).

    CAS  PubMed  Google Scholar 

  31. 31.

    Xu, Y., Smith, M. D., Krause, J. A. & Shimizu, L. S. Control of the intramolecular [2+2] photocycloaddition in a bis-stilbene macrocycle. J. Org. Chem. 74, 4874–4877 (2009).

    CAS  PubMed  Google Scholar 

  32. 32.

    Poplata, S., Tröster, A., Zou, Y.-Q. & Bach, T. Recent advances in the synthesis of cyclobutanes by olefin [2 + 2] photocycloaddition reactions. Chem. Rev. 116, 9748–9815 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  33. 33.

    Feist, J. D. & Xia, Y. Enol ethers are effective monomers for ring-opening metathesis polymerization: synthesis of degradable and depolymerizable poly(2,3-dihydrofuran). J. Am. Chem. Soc. 142, 1186–1189 (2020).

    CAS  PubMed  Google Scholar 

  34. 34.

    Royzen, M., Yap, G. P. A. & Fox, J. M. A photochemical synthesis of functionalized trans-cyclooctenes driven by metal complexation. J. Am. Chem. Soc. 130, 3760–3761 (2008).

    CAS  PubMed  Google Scholar 

  35. 35.

    Neary, W. J., Isais, T. A. & Kennemur, J. G. Depolymerization of bottlebrush polypentenamers and their macromolecular metamorphosis. J. Am. Chem. Soc. 141, 14220–14229 (2019).

    CAS  PubMed  Google Scholar 

  36. 36.

    Badamshina, E. R. et al. Investigation of the mechanism of polypentenamer degradation in the presence of metathesis catalysts. Polym. Sci. USSR 24, 164–170 (1982).

    Google Scholar 

  37. 37.

    Prelog, V. Conformation and reactivity of medium-sized ring compounds. Pure Appl. Chem. 6, 545–560 (1963).

    CAS  Google Scholar 

  38. 38.

    Burevschi, E., Peña, I. & Sanz, M. E. Medium-sized rings: conformational preferences in cyclooctanone driven by transannular repulsive interactions. Phys. Chem. Chem. Phys. 21, 4331–4338 (2019).

    CAS  PubMed  Google Scholar 

  39. 39.

    Liu, H. et al. Dynamic remodeling of covalent networks via ring-opening metathesis polymerization. ACS Macro Lett. 7, 933–937 (2018).

    CAS  Google Scholar 

  40. 40.

    Stalpaert, M. et al. Olefins from biobased sugar alcohols via selective, ru-mediated reaction in catalytic phosphonium ionic liquids. ACS Catal. 10, 9401–9409 (2020).

    CAS  Google Scholar 

  41. 41.

    Sutthasupa, S., Shiotsuki, M. & Sanda, F. Recent advances in ring-opening metathesis polymerization, and application to synthesis of functional materials. Polym. J. 42, 905–915 (2010).

    CAS  Google Scholar 

  42. 42.

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

    CAS  PubMed  Google Scholar 

  43. 43.

    Feringa, B. L. The art of building small: from molecular switches to motors (Nobel Lecture). Angew. Chem. Int. Ed. 56, 11060–11078 (2017).

    CAS  Google Scholar 

  44. 44.

    Walczak, M. A. A., Krainz, T. & Wipf, P. Ring-strain-enabled reaction discovery: new heterocycles from bicyclo[1.1.0]butanes. Acc. Chem. Res. 48, 1149–1158 (2015).

    CAS  PubMed  Google Scholar 

  45. 45.

    Agard, N. J., Prescher, J. A. & Bertozzi, C. R. A strain-promoted [3 + 2] azide−alkyne cycloaddition for covalent modification of biomolecules in living systems. J. Am. Chem. Soc. 126, 15046–15047 (2004).

    CAS  PubMed  Google Scholar 

Download references

Acknowledgements

This work is supported by the University of Akron. The computational resources were provided by Extreme Science and Engineering Discovery Environment (TG-CHE190099). The single-crystal structures were characterized with an X-ray diffractometer supported by the National Science Foundation (CHE-0840446 to C.J.Z.). We thank S. Wang for helpful discussion and K. Williams-Pavlantos and C. Wesdemiotis for conducting the MS analysis.

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Authors

Contributions

J.W. conceived the project and directed the research. D.S. and J.W. performed the density functional theory calculations and analysed the computational data. D.S., J.Z., H.C., W.X., H.-W.S. and T.-G.H. conducted the monomer and polymer syntheses. B.R.S. and C.J.Z. collected and analysed the single-crystal data. D.S. and W.X. conducted the thermodynamic studies and depolymerization. J.Z. conducted the ring-closing metathesis experiments. D.S. and J.Z. conducted the thermal characterization of the polymers. D.S. and T.S. conducted mechanical testing. D.S. and J.W. prepared the manuscript.

Corresponding author

Correspondence to Junpeng Wang.

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The authors declare no competing interests.

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Peer review information Nature Chemistry thanks Frank Leibfarth and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Materials and instrumentation, synthesis, details for polymerization and depolymerization, Supplementary Figs. 1–103, Supplementary Tables 1–5.

Supplementary Data 1

CIF file for 2; (CCDC reference: 2032007).

Supplementary Data 2

CIF file for 6; (CCDC reference: 2032008).

Supplementary Data 3

CIF file for 10; (CCDC reference: 2032009).

Source data

Source Data Fig. 3

Statistical Source Data for Fig. 3.

Source Data Fig. 5

Statistical Source Data for Fig. 5.

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Sathe, D., Zhou, J., Chen, H. et al. Olefin metathesis-based chemically recyclable polymers enabled by fused-ring monomers. Nat. Chem. 13, 743–750 (2021). https://doi.org/10.1038/s41557-021-00748-5

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