Flexible Cages Enable Robust Supramolecular Elastomers

Advanced Materials, Год журнала: 2024, Номер 36(16)

Опубликована: Янв. 6, 2024

Abstract Advances in modern industrial technology continue to place stricter demands on engineering polymeric materials, but simultaneously possessing superior strength and toughness remains a daunting challenge. Herein, pioneering flexible cage‐reinforced supramolecular elastomer (CSE) is reported that exhibits superb robustness, tear resistance, anti‐fatigue, shape memory properties, achieved by innovatively introducing organic imide cages (OICs) into networks. Intriguingly, extremely small amounts of OICs make the stronger, significantly improving mechanical (85.0 MPa; ≈10‐fold increase) (418.4 MJ m −3 ; ≈7‐fold increase). Significantly, cooperative effect gradient hydrogen bonds experimentally theoretically demonstrated as nodes, enabling more robust In short, proposed strengthening strategy adding effectively balances inherent conflict between material toughness, prepared CSEs are anticipated be served large‐scale devices such TBMs future.

Язык: Английский

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Unexpected Folding of Bottlebrush Polymers in Melts

Macromolecules, Год журнала: 2023, Номер 56(6), С. 2551 - 2559

Опубликована: Янв. 27, 2023

Bottlebrush molecules are branched polymers with a long linear backbone densely grafted by many relatively short side chains. Such unique molecular architecture enables bottlebrush properties and functions inaccessible their counterparts. The existing understanding is that, in melts of polymers, the interbackbone distance decreases as grafting density chains becomes smaller. Here, we experimentally discover behavior opposite to all works: increases monotonically decreases. To explain these remarkable experimental findings, develop theory accounting for incompatibility between within molecule. polymer folds into cylindrical core sites on its surface reduce interfacial free energy. As decreases, collapses; this process not only diameter but also reduces space, such that extension alleviated. Our discovery presents paradigm-shifting structure polymers.

Язык: Английский

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Acid-Induced Gelation of Carboxymethylcellulose Solutions

ACS Macro Letters, Год журнала: 2024, Номер unknown, С. 234 - 239

Опубликована: Фев. 1, 2024

The present work offers a comprehensive description of the acid-induced gelation carboxymethylcellulose (CMC), water-soluble derivative cellulose broadly used in numerous applications ranging from food packaging to biomedical engineering. Linear viscoelastic properties measured at various pH and CMC contents allow us build sol–gel phase diagram show that gels exhibit broad power-law spectra can be rescaled onto master curve following time–composition superposition principle. These results demonstrate microstructural self-similarity inspire mean-field model based on hydrophobic interchain association accounts for boundary over entire range content under study. Neutron scattering experiments further confirm this picture suggest comprise fibrous network cross-linked by aggregates. Finally, low-field NMR measurements offer an original signature solvent perspective. Altogether, these open avenues precise manipulation control CMC-based hydrogels.

Язык: Английский

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3D Printable Modular Soft Elastomers from Physically Cross-linked Homogeneous Associative Polymers

ACS Polymers Au, Год журнала: 2024, Номер 4(2), С. 98 - 108

Опубликована: Янв. 4, 2024

Three-dimensional (3D) printing of elastomers enables the fabrication many technologically important structures and devices. However, there remains a critical need for development reprocessable, solvent-free, soft that can be printed without post-treatment. Herein, we report modular suitable direct ink writing (DIW) by physically cross-linking associative polymers with high fraction reversible bonds. We designed synthesized linear-associative-linear (LAL) triblock copolymers; middle block is an polymer carrying amide groups form double hydrogen bonding, end blocks aggregate to hard glassy domains effectively act as physical cross-links. The do not nanoscale clusters only slow down dynamics changing shape linear viscoelastic spectra; this molecular control over energy dissipation varying groups. Increasing volume increases network stiffness more than 100 times significantly compromising extensibility. created Young's moduli ranging from 8 kPa MPa while maintaining tensile breaking strain around 150%. Using high-temperature DIW platform, transformed our complex, highly deformable 3D involving any solvent or post-print processing. Our represent softest melt reprocessable materials printing. developed LAL synergize emerging homogeneous bonds classical copolymer self-assembly dual-cross-linked network, providing versatile platform design elastomeric practical applications.

Язык: Английский

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Capturing Robust and Tough Thermoplastic Polyurethane Elastomers via Engineering Dual-Phase Evolution Rather than Chain Extenders

ACS Materials Letters, Год журнала: 2025, Номер unknown, С. 2238 - 2245

Опубликована: Май 14, 2025

Язык: Английский

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Nonuniversal Dynamics of Hyperbranched Metallo-Supramolecular Polymer Networks by the Spontaneous Formation of Nanoparticles

ACS Nano, Год журнала: 2024, Номер 18(42), С. 29282 - 29293

Опубликована: Окт. 14, 2024

Various transient and permanent bonds are commonly combined in increasingly complex hierarchical structures to achieve biomimetic functions, along with high mechanical properties. However, there is a traditional trade-off between strength biological functions like self-healing. To fill this gap, we develop metallo-supramolecular polymer hydrogel based on the hyperbranched poly(ethylene imine) (PEI) backbone phenanthroline ligands, which have unexpectedly plateau modulus at low concentrations. Rheological measurements demonstrate nonuniversal metal-ion-specific dynamics, significantly larger moduli, longer relaxation times, stronger temperature dependencies, compared equivalent networks model-type telechelic precursors, cannot be explained by theory of linear viscoelasticity. TEM images reveal

Язык: Английский

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Coupling and Decoupling between Stickers and Backbones in Associating Polymers with Terminally Functionalized Side Chains

Macromolecules, Год журнала: 2024, Номер unknown

Опубликована: Авг. 15, 2024

Associating polymers have recently attracted tremendous attention as self-healing due to the dynamic reversibility of sticker association–dissociation processes. These dynamics inevitably slow significantly segmental decelerate below glass transition temperature that limits operational temperatures associating polymers. Using broadband dielectric spectroscopy on a new set composed side chains various lengths and terminal carboxylic-acid functionality, we discovered an unexpected decoupling near (Tg) between slower backbone fast motions. two motions distinct activation energies for motion sulfur linkage adjacent (∼22 26 kJ/mol) carboxylic acid groups (∼5 8 kJ/mol). A second appears in polymer with longest chain length at Tg – 20 K, reflecting binding configurations. Our findings open door design capability association/dissociation low temperatures.

Язык: Английский

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The explicit bonding reaction ensemble Monte Carlo method

The Journal of Chemical Physics, Год журнала: 2024, Номер 161(9)

Опубликована: Сен. 3, 2024

We present the explicit bonding Reaction ensemble Monte Carlo (eb-RxMC) method, designed to sample reversible reactions in macromolecular systems thermodynamic equilibrium. Our eb-RxMC method is based on reaction method; however, its implementation differs from latter by representation of reaction. In implementation, we are adding or deleting bonds between existing particles, instead inserting particles with different chemical identities. This new makes suitable for simulating formation linkages macromolecules, which would not be feasible original implementation. To enable coupling our algorithm molecular dynamics sampling configuration space, biased only within a certain inclusion radius. validated using set ideally behaving undergoing dimerization and polycondensation reactions, analytical results available. For various equilibrium constants initial compositions, degree conversion measured simulations perfectly matched reference values given equations. also showed that this agreement affected arbitrary choice radius stiffness harmonic bond potential. Next, can correctly match distribution polymerization end-to-end distance ideal chains reactions. Altogether, demonstrated both spaces these systems, opening door future more complex interacting systems.

Язык: Английский

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Bond Density Not Strength Controls Polymer Stickiness

Physics, Год журнала: 2023, Номер 16

Опубликована: Май 31, 2023

Experiments show that the sticky behavior of

Язык: Английский

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3D Printable Modular Soft Elastomers from Physically Crosslinked Homogeneous Associative Polymers

Опубликована: Авг. 25, 2023

Three-dimensional (3D) printing of elastomers enables the fabrication many technologically important structures and devices. However, there remains a critical need for development reprocessable, solvent-free soft that can be printed without post-treatment. Here, we report modular suitable direct ink write (DIW) by physically crosslinking associative polymers with high fraction reversible bonds. We design synthesize linear-associative-linear (LAL) triblock copolymers; middle block is an polymer carrying amide groups form double hydrogen bonding, end blocks aggregate to hard glassy domains effectively act as physical crosslinks. The do not nanoscale clusters only slow dynamics changing shape linear viscoelastic spectra; this molecular control over energy dissipation varying groups. Exploiting more ordered microstructures afforded copolymer self-assembly increases network stiffness >100 times significantly compromising extensibility. use high-temperature DIW platform print these LAL manufacture complex, highly deformable 3D structures. Our process uses melt processing solvent-free, parts require any post-print processing. create Young’s moduli ranging from 8 kPa MPa while maintaining tensile breaking strain around 150%. represent softest reprocessable materials printing. developed synergize emerging homogeneous bonds classical dual-crosslinked network, providing versatile soft, elastomeric practical applications.

Язык: Английский

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