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Nature Chemistry (2022 )Cite this article Metal Dihydride

Geminal disubstitution of cyclic monomers is an effective strategy to enhance the chemical recyclability of their polymers, but it is utilized for that purpose alone and often at the expense of performance properties. Here we present synergistic use of gem-α,α-disubstitution of available at-scale, bio-based δ-valerolactones to yield gem-dialkyl-substituted valerolactones (\({\rm{VL}}^{{\rm{R}}_{2}}\) ), which generate polymers that solve not only the poor chemical recyclability but also the low melting temperature and mechanical performance of the parent poly(δ-valerolactone); the gem-disubstituted polyesters (\({\rm{PVL}}^{{\rm{R}}_{2}}\) ) therefore not only exhibit complete chemical recyclability but also thermal, mechanical and transport properties that rival or exceed those of polyethylene. Through a fundamental structure–property study that reveals intriguing impacts of the alkyl chain length on materials performance of \({\rm{PVL}}^{{\rm{R}}_{2}}\) , this work establishes a simple circular, high-performance polyester platform based on \({\rm{VL}}^{{\rm{R}}_{2}}\) and highlights the importance of synergistic utilization of gem-disubstitution for enhancing both chemical recyclability and materials performance of sustainable polyesters.
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The work performed at Dalian University of Technology was supported by the National Natural Science Foundation of China (grant no. 21774017) and the Fundamental Research Funds for the Central Universities (grant no. DUT20LK35). The work performed at Colorado State University was supported by RePLACE (Redesigning Polymers to Leverage A Circular Economy) funded by the Office of Science of the US Department of Energy via award no. DE-SC0022290.
State Key Laboratory of Fine Chemicals, Department of Chemistry, School of Chemical Engineering, Dalian University of Technology, Dalian, China
Xin-Lei Li, Jing-Yang Jiang & Tie-Qi Xu
Department of Chemistry, Colorado State University, Fort Collins, CO, USA
Ryan W. Clarke & Eugene Y.-X. Chen
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X.-L.L., T.-Q. X. and E.Y.-X.C. conceived the idea and designed the experiments. X.-L.L., R.W.C. and J.-Y.J. performed the experiments, and analysed and processed the data. All authors co-wrote the manuscript and participated in data analyses and discussions.
Correspondence to Tie-Qi Xu or Eugene Y.-X. Chen.
T.X. and X.L. are named inventors on a Chinese patent application submitted by Dalian University of Technology that covers the polyester based on α,α-disubstituted valerolactones as well as the their preparation method and degradation. E.Y.-X.C. is a named inventor on a US patent application submitted by Colorado State University Research Foundation, which covers chemically circular semi-crystalline polyesters. The other authors declare no competing interests.
Nature Chemistry thanks Joshua Worch and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Li, XL., Clarke, R.W., Jiang, JY. et al. A circular polyester platform based on simple gem-disubstituted valerolactones. Nat. Chem. (2022). https://doi.org/10.1038/s41557-022-01077-x
DOI: https://doi.org/10.1038/s41557-022-01077-x
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