Abstract
Enhancing the toughness while achieving triggerable degradation in single-network polymer systems without modifying their inherent chemical composition or network architecture remains a significant challenge. Here we demonstrate a smart end-linked polymer network that “self-strengthen” during use yet “self-destruct” upon certain stimuli. Embedding nonscissile cyclobutane-fused tetrahydrofuran mechanophores within the middle of end-linked polymer networks significantly enhances both toughness and degradability. Under mechanical stress, the force-coupled cycloreversion of these mechanophores releases concealed chain segments, enabling single-network materials to exhibit threefold toughness and tenfold tear energies compared to conventional counterparts. Additionally, ball-milling griding of the bulk material unveils acid-sensitive enol ether units, leading to a markedly improved degradation profile under acidic conditions. This dual effect—originating from the force-coupled cycloreversion of cyclobutane-fused tetrahydrofuran mechanophores—provides an ideal combination of superior mechanical performance and on-demand degradability.
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All the other data supporting the findings of this study are available within the article and its Supplementary Information. All data are available from the corresponding author upon request.
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Acknowledgements
This research was supported by the National Natural Science Foundation of China (52473097, 22401187) and the Fundamental Research Funds for the Central Universities (25X010202131). We thank Prof. G. Tong (SJTU) for the help with FTIR-ATR and rheological measurements, Prof. X. Yan (SJTU) for the technical help with tensile strength measurements.
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S.T. contributed to the conception and design of the experiments. Z.L. performed the experiments. S.T. and Z.L. cowrote the manuscript, and S.T. directed the project.
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Li, Z., Tang, S. Cycloreversion-enhanced toughness and degradability in mechanophore-embedded end-linked polymer networks. Nat Commun (2026). https://doi.org/10.1038/s41467-025-68268-1
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DOI: https://doi.org/10.1038/s41467-025-68268-1
