Tunable and Degradable Dynamic Thermosets from Compatibilized Polyhydroxyalkanoate Blends

Ling, Chen [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); Xiamen Univ. (China)]; Clarke, Ryan W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)] (ORCID:0000000210833618); Rosetto, Gloria [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center]; Xu, Shu [Argonne National Laboratory (ANL), Argonne, IL (United States); Northwestern Argonne Institute of Science & Engineering, Evanston, IL (United States)] (ORCID:0000000227137897); Cywar, Robin M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center]; Kim, Dong Hyun [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center]; Hamernik, Levi J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center]; Haugen, Stefan J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)]; Michener, William E. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); BOTTLE Consortium, Golden, CO (United States)]; Woodworth, Sean P. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)] (ORCID:0000000337929553); Lind, Torrey M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States)]; Ramirez, Kelsey J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); BOTTLE Consortium, Golden, CO (United States)]; Urgun-Demirtas, Meltem [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000315811554); Salvachúa, Davinia [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States)] (ORCID:000000030799061X); Johnson, Christopher W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States)] (ORCID:0000000229794751); Rorrer, Nicholas A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)] (ORCID:0000000191345853); Beckham, Gregg T. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); BOTTLE Consortium, Golden, CO (United States)] (ORCID:000000023480212X)

doi:10.1021/acssuschemeng.5c00943

DOE OSTI · 2545697

Tunable and Degradable Dynamic Thermosets from Compatibilized Polyhydroxyalkanoate Blends

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Abstract

Polyhydroxyalkanoates (PHAs) are versatile, biobased polyesters that are often targeted for use as degradable thermoplastic replacements for polyolefins. Given the substantial chemical diversity of PHA, their potential as cross-linked polymers could also enable similar platforms for reversible, degradable thermosets. In this work, we genetically engineered Pseudomonas putida KT2440 to synthesize poly(3-hydroxybutyrate-co-3-hydroxyundecenoate) (PHBU), which contains both 3-hydroxybutyrate and unsaturated 3-hydroxyundecenoate components. To reduce the brittleness of this polymer, we physically blended PHBU with the soft copolymer poly(3-hydroxydecanonate-co-3-hydroxyundecenoate) in mass ratios of 1:3, 1:1, and 3:1. Upon observing varying degrees of immiscibility by scanning electron microscopy, we installed dynamic boronic ester cross-links via thiol–ene click chemistry, which resulted in compatibilized dynamic thermoset blends ranging in hard, medium, and soft rubber or elastomer thermomechanical profiles. These dynamic thermoset blends were subjected to controlled biological degradation experiments in freshwater conditions, achieving timely mass loss despite the cross-linked architectures. Overall, this work highlights a two-component platform for the production of degradable and reprocessable dynamic thermoset blends suitable for several classes of cross-linked polymer technologies from tailored, biological PHA copolymers.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY PHA biobased polymer biodegradable polymer metabolic engineering microbial synthesis vitrimer

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Ling, Chen [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); Xiamen Univ. (China)], Clarke, Ryan W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)] (ORCID:0000000210833618), Rosetto, Gloria [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center], Xu, Shu [Argonne National Laboratory (ANL), Argonne, IL (United States); Northwestern Argonne Institute of Science & Engineering, Evanston, IL (United States)] (ORCID:0000000227137897), Cywar, Robin M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center], Kim, Dong Hyun [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center], Hamernik, Levi J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center], Haugen, Stefan J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)], Michener, William E. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); BOTTLE Consortium, Golden, CO (United States)], Woodworth, Sean P. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)] (ORCID:0000000337929553), Lind, Torrey M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States)], Ramirez, Kelsey J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); BOTTLE Consortium, Golden, CO (United States)], Urgun-Demirtas, Meltem [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000315811554), Salvachúa, Davinia [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States)] (ORCID:000000030799061X), Johnson, Christopher W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States)] (ORCID:0000000229794751), Rorrer, Nicholas A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; BOTTLE Consortium, Golden, CO (United States)] (ORCID:0000000191345853), Beckham, Gregg T. [National Renewable Energy Laboratory (NREL), Golden, CO (United States). Renewable Resources and Enabling Science Center; USDOE Agile BioFoundry, Emeryville, CA (United States); BOTTLE Consortium, Golden, CO (United States)] (ORCID:000000023480212X). 2025-02-27. Tunable and Degradable Dynamic Thermosets from Compatibilized Polyhydroxyalkanoate Blends. https://doi.org/10.1021/acssuschemeng.5c00943

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