Synthesis, Recycling and High‐Throughput Reprocessing of Phase‐Separated Vitrimer‐Thermoplastic Blends

Advanced Functional Materials, Год журнала: 2023, Номер 34(1)

Опубликована: Сен. 28, 2023

Abstract Phase‐separated polymer blends including a transesterification vitrimer and polypropylene are synthesized from widely available precursors through reactive processing. It is shown that proper formulation during the process viscosity modifier of interface compatibilizer yields well‐dispersed phases with fractions up to 75 wt.% in phase. These can be easily reprocessed by multiple shredding‐injection cycles processed high‐shear conditions capillary rheometry. Rheological analyses reveal percolating dynamic network formed across domains. breaks apart high shear reprocessing material dynamically reforms after thermal annealing blends. therefore ideally combines mechanical high‐throughput (re)processing properties thermoplastic matrix minor phase chemical, thermomechanical, major This work illustrates decoupling processing at rates enabled aid kinetics exchanges thermomechanical service temperature

Язык: Английский

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Aza-Michael Chemistry for PDMS-Based Covalent Adaptable Elastomers: Design and Dual Role of the Silica Filler

Macromolecules, Год журнала: 2024, Номер 57(10), С. 4817 - 4825

Опубликована: Май 7, 2024

In this study, polydimethylsiloxane (PDMS)-based covalent adaptable networks have been prepared in a one-pot, catalyst-free way which dynamic β-amino esters (BAEs) are introduced via aza-Michael addition between available acrylate/amine-terminated PDMS-compounds. The straightforward introduction of those BAE-groups such high-value elastomers provides the ability to relax applied stress at elevated temperatures and hence capability reshaping by compression molding least 5 times without significant changes properties. Moreover, mechanical properties tunable varying cross-linker and/or filler content. Interestingly, utilization silica fillers not only enhances network formation but also accelerates exchange reactions, resulting twice faster relaxation while maintaining creep resistance service temperatures.

Язык: Английский

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Improving the Thermomechanical Properties and Processability of Elastomeric Vitrimers Using Thermoreversible Organic Nanofillers

ACS Materials Letters, Год журнала: 2024, Номер 6(3), С. 877 - 884

Опубликована: Фев. 8, 2024

Vitrimers are a promising class of polymer networks that feature thermally activated dynamic covalent bonds. Although for many applications in material science, vitrimers tend to be difficult process because high viscosity. Processability is commonly enhanced at the expense mechanical performance service temperature, and thus this trade-off remains an important challenge development these materials. Herein, we report new approach based on thermoreversible organic nanofillers (TRONs), which define as low molar mass molecules act reinforcing fillers temperature plasticizers processing temperature. This concept exemplified context elastomeric dioxaborolane-based polybutadiene vitrimer model matrix, two different dibenzylidene sorbitol derivatives evaluated TRONs. We find loaded with TRONs exhibit improved creep resistance tensile properties temperatures while also exhibiting lower viscosity temperatures.

Язык: Английский

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Chemical degradation of oxygenated polymers: the case of polyethers and polysiloxanes

RSC Sustainability, Год журнала: 2024, Номер 2(7), С. 1904 - 1929

Опубликована: Янв. 1, 2024

A review of the most representative advances in chemical degradation polythers and polysiloxanes, both academia industry.

Язык: Английский

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Linear Viscoelasticity of Polystyrene Vitrimers: Segmental Motions and the Slow Arrhenius Process

Macromolecules, Год журнала: 2025, Номер unknown

Опубликована: Апрель 4, 2025

Язык: Английский

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Integrated Extrinsic and Intrinsic Self‐Healing of Polysiloxane Materials by Cleavable Molecular Cages Encapsulating Fluoride Ions

Advanced Science, Год журнала: 2023, Номер 10(27)

Опубликована: Июль 28, 2023

Abstract Self‐healing ability is crucial to increasing the lifetime and reliability of materials. In this study, spatiotemporal control healing a polysiloxane material achieved using cleavable cage compound encapsulating fluoride ion (F − ), which triggeres dynamic rearrangement siloxane (Si–O–Si) networks. A self‐healing siloxane‐based elastomer prepared by cross‐linking polydimethylsiloxane (PDMS) with F ‐encapsulating cage‐type germoxane (Ge–O–Ge) compound. This can self‐heal repeatedly under humid conditions. The released hydrolytic cleavage framework contributes rejoining cut pieces promoting local use molecular catalyst for bond provides new concept designing materials based on integrated extrinsic intrinsic mechanisms.

Язык: Английский

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Trialkoxysilane Exchange: Scope, Mechanism, Cryptates and pH‐Response

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(26)

Опубликована: Апрель 28, 2023

Abstract The dynamic covalent chemistry (DCvC) of the Si−O bond holds unique opportunities, but has rarely been employed to assemble discrete molecular architectures. This may be due harsh conditions required initiate exchange reactions at silicon in aprotic solvents. Herein, we provide a comprehensive experimental and computational account on reaction trialkoxysilanes with alcohols identify mild for rapid Substituent, solvent salt effects are uncovered, understood exploited construction sila‐orthoester cryptates. A sharp, divergent pH‐response obtained cages renders this substance class attractive future applications well beyond host‐guest chemistry, instance, drug delivery.

Язык: Английский

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Advancing Recyclable Thermosets through C═C/C═N Dynamic Covalent Metathesis Chemistry

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(31), С. 21612 - 21622

Опубликована: Июль 24, 2024

Thermoset polymers have become integral to our daily lives due their exceptional durability, making them feasible for a myriad of applications; however, this ubiquity also raises serious environmental concerns. Covalent adaptable networks (CANs) with dynamic covalent linkages that impart efficient reprocessability and recyclability thermosets garnered increasing attention. While various exchange reactions been explored in CANs, many rely on the stimuli active nucleophilic groups and/or catalysts, introducing performance instability escalating initial investment. Herein, we propose new direct catalyst-free C═C/C═N metathesis reaction between α-cyanocinnamate aldimine as novel motif constructing recyclable thermosets. This chemistry offers mild conditions (room temperature catalyst-free), ensuring high yields simple isolation procedures. By incorporating into covalently cross-linked polymer networks, obtained exhibit both malleability reconfigurability. The resulting tunable properties, coupled thermal stability linkage-based enrich toolbox chemistry.

Язык: Английский

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Self-healing materials based on dynamic properties of siloxane networks

Journal of Sol-Gel Science and Technology, Год журнала: 2025, Номер unknown

Опубликована: Апрель 7, 2025

Язык: Английский

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Dynamic Covalent Chemistry in Rubber Crosslinking

Royal Society of Chemistry eBooks, Год журнала: 2025, Номер unknown, С. 31 - 75

Опубликована: Апрель 28, 2025

As a typical class of thermosets, rubbers suffer from great challenges in recycling and reuse. Incorporating dynamic covalent chemistry (DCC) into rubber crosslinking provides very promising cradle-to-cradle solution to this issue. Rubbers crosslinked with bonds can reshuffle their network topology at elevated temperatures, endowing fascinating properties, such as self-healing, welding, reshaping, reprocessing, while maintaining good stability enabled by the bonds. To date, diverse DCCs have been introduced rubbers. In chapter, simple introduction DCC adaptable networks is first given, followed an overview application according categories DCCs. The mechanisms various effects on performance are interpreted. At last, conclusion made some perspectives possible that need be overcome for practical

Язык: Английский

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