Precise placement of thioester bonds into sequence-controlled polymers containing ABAC-type units

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 25, 2025

The precise placement of thioester bonds into sequence-controlled polymers remains a grand challenge. Here, we demonstrate the versatile synthesis from step polymerization cyclic thioanhydrides (A), diacrylates (B), and diols/diamines (C). In addition to easily accessible diverse monomers, method is metal-free/catalyst-free, atom-economical, wide in monomer scope, yielding 107 with >90% yields weight-average molecular weights up 175.4 kDa. obtained contain ABAC-type repeating units precisely distributed in-chain ester (and amide) groups. chemoselectivity revealed by density functional theory calculations. polymer library exhibits considerably tunable performance: glass-transition temperatures −36–72 °C, melting 43–133 degradability, thermoplastics/elastomers, thioester-based functions. This study furnishes facile incorporate polymers. challenging. authors thioanhydrides, diacrylates, diols/diamines.

Language: Английский

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Ultratough Thermoplastic Elastomers Based on Chemically Recyclable Cycloalkyl-Substituted Polyhydroxyalkanoates

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: 147(9), P. 7788 - 7798

Published: Feb. 20, 2025

It remains a long-standing challenge for chemical recycling of polyhydroxyalkanoates (PHAs) to propiolactone-based monomers due the high ring strain and many inevitable side reactions. In this contribution, novel α-spiro-cyclohexyl-propiolactone (SHPL) has been designed with reactivity toward ring-opening polymerization even at catalyst loading <1 ppm. The resulting poly(3-hydroxy-2-spiro-cyclohexylpropionate) (P3HSHP) exhibited thermal stability Td 364 °C Tm 272 °C. Meanwhile, it could be depolymerized back SHPL in 86% yield without decarboxylation or elimination products. Notably, exploited construct high-performance thermoplastic elastomers (TPEs) via one-pot copolymerization ε-caprolactone (CL). Particularly, gradient P(CL2000-grad-SHPL500) showcased an ultimate tensile strength 58.8 ± 4.0 MPa, stretchability 1959 53%, record toughness 600 MJ/m3, elastic recovery (>90%). This superior performance advance development new sustainable TPEs.

Language: Английский

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Strong Bases and beyond: The Prominent Contribution of Neutral Push–Pull Organic Molecules towards Superbases in the Gas Phase

International Journal of Molecular Sciences, Journal Year: 2024, Volume and Issue: 25(11), P. 5591 - 5591

Published: May 21, 2024

In this review, the principles of gas-phase proton basicity measurements and theoretical calculations are recalled as a reminder how PA/GB scale, based on Brønsted–Lowry theory, was constructed in (PA—proton affinity and/or GB—gas-phase enthalpy Gibbs energy respectively). The origins exceptionally strong some organic nitrogen bases containing N-sp3 (amines), N-sp2 (imines, amidines, guanidines, polyguanides, phosphazenes), N-sp (nitriles) rationalized. particular, role push–pull development superbasicity region is emphasized. Some reasons for difficulties poly-functional highlighted. Various structural phenomena being relation with acid–base equilibria that should be considered quantum-chemical parameters discussed. preparation methods site protonation briefly reviewed. Finally, recent trends research neutral superbases, leaning toward catalytic other remarkable applications, underlined.

Language: Английский

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A Pseudo-Block Copolymerization Access to Cyclic Alternating Copolymers through Segment-Selective Transesterification

ACS Macro Letters, Journal Year: 2025, Volume and Issue: unknown, P. 142 - 148

Published: Jan. 21, 2025

Efficient synthesis of cyclic polymers remains a frontier challenge. We report here that macromolecular transesterification during pseudoblock copolymerization process can be utilized for such purpose. Organobase-catalyzed ring-opening alternating 3,4-dihydrocoumarin and epoxide is conducted with four-armed poly(ethylene oxide) (PEO) as macroinitiator. Intramolecular (backbiting) occurs selectively on the newly formed polyester segments. The disconnected copolymers easily isolated by precipitation owing to their substantial solubility difference from PEO-containing acyclic parts. obtained exhibit low dispersity (<1.2) molar mass around 3 kg mol–1, irrespective monomer-to-initiator feed ratio, indicating thermodynamic control over ring size. macrocyclic structure confirmed both spectroscopy microscopic visualization then prepare cyclic-brush terpolymer thiol–ene modification, followed graft polymerization propylene oxide.

Language: Английский

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Circularity in polydiketoenamine thermoplastics via control over reactive chain conformation

Science Advances, Journal Year: 2025, Volume and Issue: 11(4)

Published: Jan. 22, 2025

Controlling the reactivity of bonds along polymer chains enables both functionalization and deconstruction with relevance to chemical recycling circularity. Because substrate is a macromolecule, however, understanding effects chain conformation on emerges as important yet underexplored. Here, we show how oxy-functionalization chemically recyclable condensation polymers affects acidolysis monomers through control over distortion interaction energies in rate-limiting transition states. Oxy-functionalization polydiketoenamines at specific sites either amine or triketone monomer segments increased rates by more than three orders magnitude, opening door efficient linear architectures. These insights substantially broaden scope applications for circular manufacturing economy, including adhesives diverse range surfaces.

Language: Английский

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Cyclic Poly(Thioester Amide)s via Ring-Opening Copolymerization of Aziridines and Phthalic Thioanhydride: Mechanistic Insights and Enhanced Properties for Sustainable Materials

Macromolecules, Journal Year: 2025, Volume and Issue: unknown

Published: May 7, 2025

Language: Английский

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High-performance recyclable polymers enabled by stereo- and sequence-controlled polymerization

Nature Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: May 16, 2025

Language: Английский

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Biobased Cyclic Polycarbonate: Synthesis and Applications via Dynamic Bis(hindered amino)disulfide Linkers

ACS Macro Letters, Journal Year: 2025, Volume and Issue: unknown, P. 750 - 756

Published: May 17, 2025

Cyclic polymers have garnered significant interest due to their unique structure; however, synthesis remains challenging, often hindered by low yields and limited selectivity. Considering that the cyclization step during of cyclic is presumably most using a spontaneous selective system ideal. Here, we present topology transformation from linear cyclic, which achieved through error-checking ability provided dynamic covalent bonding between bis(2,2,6,6-tetramethylpiperidin-1-yl)disulfide (BiTEMPS) its stable radicals with high bond exchange rate. When applying this method biobased poly(isosorbide carbonate) (PIC), an attractive alternative conventional petroleum-based polycarbonates, high-molecular-weight were unexpectedly obtained. Since functionalization PICs has been traditionally copolymerization techniques, aimed introduce bonds establish novel methods for PICs. Interestingly, intramolecular in heterogeneous proceeded via ring-expansion polymerization-like mechanism, affording consisting PIC backbone BiTEMPS units as units. The resulting PIC-based applied reactions, providing effective approach block end-functionalized skeleton. These results demonstrate potential chemistry polymer synthesis.

Language: Английский

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Ring-opening Polymerization of Benzo-fused Thiolactones toward Chemically Recyclable Semi-aromatic Polythioesters

Chinese Journal of Polymer Science, Journal Year: 2025, Volume and Issue: unknown

Published: May 20, 2025

Language: Английский

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Fluorescence sensing of water in various organic solvents based on a novel cyclic polymer

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy, Journal Year: 2024, Volume and Issue: 319, P. 124554 - 124554

Published: May 31, 2024

Language: Английский

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