Abstract
Developing polymer matrices with closed-loop recyclability is a key solution to solve the sustainability issues caused by unrecyclable end-of-life multi-phase composites, and using building blocks from renewable resources rather than petrochemical products presents an attractive option. However, the strategy of first extracting monomers from biomass feedstocks and then polymerizing them is functionality-removed, complexity-increased, and energy-inputted. We report a strategy demonstration from current polymer-monomer-matrix mode to polymer-macromolecule-matrix, based on retaining the advantages in property, processing, and recycling of silk protein. The silk matrix as was its fiber-reinforced composite show spontaneously room-temperature molding and curing capabilities, totally avoiding the use of any additives. The obtained composites also possess high mechanical property and environmental durability. Moreover, the multicycle recyclability of composites could be achieved by a simple room-temperature dissolution procedure, acquiring lossless reinforcing fibers and reusable silk protein.
Data availability
The data generated in this study are provided in the Supplementary Information and Source Data file. All data are available from the corresponding author upon request. Source data are provided with this paper.
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Acknowledgments
This work was supported by the National Natural Science Foundation of China (Grant No. 52103149 to Z.X.), Zhejiang Provincial Natural Science Foundation of China (Grant No. LMS25C170001 to Z.X.), National Key R&D Program of China (Grant No. 2023YFF1103900 to M.Y.), State of Sericulture Industry Technology System (Grant No. CARS-18-ZJ0501 to M.Y.), and Zhejiang University start-up fund (to Z.X.). We would like to thank Tiancheng Wei, Meidan Zheng, Bo Jiang, and Zhixiang Xu from Zhejiang University for their helpful experimental guidance. Furthermore, we would like to thank Ms. Lijuan Mao from the Analysis Center of Agrobiology and Environmental Sciences, Zhejiang University, for her help with FTIR analysis.
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F.H. contributed to the methodology, investigation, visualization, and writing the original draft. S.Y. contributed to the methodology. H. L. contributed to the visualization. Q.W., Y.S., J.W., and M.L. contributed to writing the review and editing. M.Y. contributed to writing the review and editing, supervision, project administration and funding acquisition. Z.X. contributed to the conceptualization, methodology, investigation, visualization, writing the original draft, writing the review and editing, supervision, project administration and funding acquisition.
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He, F., Ying, S., Liu, H. et al. A strategy for biomass-derived matrix with facile moulding and closed-loop recycling capabilities. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69813-2
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DOI: https://doi.org/10.1038/s41467-026-69813-2
