Elastomeric vitrimers from designer polyhydroxyalkanoates with recyclability and biodegradability

Cywar, Robin M.; Ling, Chen; Clarke, Ryan W.; Kim, Dong Hyun; Kneucker, Colin M.; Salvachúa, Davinia; Addison, Bennett; Hesse, Sarah A.; Takacs, Christopher J.; Xu, Shu; Demirtas, Meltem Urgun; Woodworth, Sean P.; Rorrer, Nicholas A.; Johnson, Christopher W.; Tassone, Christopher J.; Allen, Robert D.; Chen, Eugene Y.-X.; Beckham, Gregg T.

doi:10.1126/sciadv.adi1735

DOE OSTI · 2280788

Elastomeric vitrimers from designer polyhydroxyalkanoates with recyclability and biodegradability

Cywar, Robin M.·Ling, Chen·Clarke, Ryan W.·Kim, Dong Hyun·Kneucker, Colin M.·Salvachúa, Davinia·Addison, Bennett·Hesse, Sarah A.·Takacs, Christopher J.·Xu, Shu·Demirtas, Meltem Urgun·Woodworth, Sean P.·Rorrer, Nicholas A.·Johnson, Christopher W.·Tassone, Christopher J.·Allen, Robert D.·Chen, Eugene Y.-X.·Beckham, Gregg T.

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Abstract

Cross-linked elastomers are stretchable materials that typically are not recyclable or biodegradable. Medium-chain-length polyhydroxyalkanoates (mcl-PHAs) are soft and ductile, making these bio-based polymers good candidates for biodegradable elastomers. Elasticity is commonly imparted by a cross-linked network structure, and covalent adaptable networks have emerged as a solution to prepare recyclable thermosets via triggered rearrangement of dynamic covalent bonds. Here, we develop biodegradable and recyclable elastomers by chemically installing the covalent adaptable network within biologically produced mcl-PHAs. Specifically, an engineered strain of Pseudomonas putida was used to produce mcl-PHAs containing pendent terminal alkenes as chemical handles for postfunctionalization. Thiol-ene chemistry was used to incorporate boronic ester (BE) cross-links, resulting in PHA-based vitrimers. mcl-PHAs cross-linked with BE at low density (<6 mole %) affords a soft, elastomeric material that demonstrates thermal reprocessability, biodegradability, and denetworking at end of life. The mechanical properties show potential for applications including adhesives and soft, biodegradable robotics and electronics.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY PHAs bio-based biodegradable elastomeric vitrimers polyhydroxyalkanoates recyclable soft elastomer recyclable soft elastomer with potential application in robotics and electronics

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Cywar, Robin M., Ling, Chen, Clarke, Ryan W., Kim, Dong Hyun, Kneucker, Colin M., Salvachúa, Davinia, Addison, Bennett, Hesse, Sarah A., Takacs, Christopher J., Xu, Shu, Demirtas, Meltem Urgun, Woodworth, Sean P., Rorrer, Nicholas A., Johnson, Christopher W., Tassone, Christopher J., Allen, Robert D., Chen, Eugene Y.-X., Beckham, Gregg T.. 2023-11-22. Elastomeric vitrimers from designer polyhydroxyalkanoates with recyclability and biodegradability. https://doi.org/10.1126/sciadv.adi1735

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