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DOE OSTI · 3377834

Leveraging Stereochemistry to Optimize the Properties of Polyhydroxyalkanoates

Young, Morgan S. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000228011970)·Rusconi, Yolanda [Scuola Superiore Meridionale, Naples (Italy); University of Naples Federico II (Italy)] (ORCID:0009000694438944)·LaPointe, Anne M. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000278300922)·Keresztes, Ivan [Cornell University, Ithaca, NY (United States)] (ORCID:0000000212713847)·Talarico, Giovanni [Scuola Superiore Meridionale, Naples (Italy); University of Naples Federico II (Italy)] (ORCID:0000000248610444)·Coates, Geoffrey W. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000234002552)
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Abstract

The recycling of low-density polyethylene (LDPE) is challenging due to difficulties with sorting and contamination, leading to environmental harm. Polyhydroxyalkanoates (PHAs) are at the forefront of high-performance biodegradable alternatives to olefinic plastics, but few offer LDPE-like properties such as low strength and crystallinity while maintaining high ductility and thermal stability. Herein, we report a series of isoenriched transpoly( 3-hydroxy-2-methylbutyrates) (trans-PHMBs) with tunable mechanical and thermal properties. These polymers were synthesized through ring-opening polymerization of racemic trans-3,4-dimethylpropiolactone (rac-trans-DMPL), sourced from C1 and C4 feedstocks, using a new class of “sandwich” C 2 symmetric rac-( Ar BDI*)ZnO i Pr catalysts (where BDI = β-diketiminate). Variation of aromatic groups (Ar) and polymerization temperature yielded mm%s between 45−79% and melting temperatures (T m ) between 141−174 °C. trans-PHMB with intermediate isotacticities of 73 and 75 mm% exhibit similar stress−strain profiles to LDPE, indicating that these polymers have the potential to serve as higher melting, degradable substitutes for LDPE.

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Young, Morgan S. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000228011970), Rusconi, Yolanda [Scuola Superiore Meridionale, Naples (Italy); University of Naples Federico II (Italy)] (ORCID:0009000694438944), LaPointe, Anne M. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000278300922), Keresztes, Ivan [Cornell University, Ithaca, NY (United States)] (ORCID:0000000212713847), Talarico, Giovanni [Scuola Superiore Meridionale, Naples (Italy); University of Naples Federico II (Italy)] (ORCID:0000000248610444), Coates, Geoffrey W. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000234002552). 2026-06-17. Leveraging Stereochemistry to Optimize the Properties of Polyhydroxyalkanoates. https://doi.org/10.1021/jacs.6c08149

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