Reaction of β‐Ketoester and 1,3‐Diol to Access Chemically Recyclable and Mechanically Robust Poly(vinyl alcohol) Thermosets through Incorporation of β‐(1,3‐dioxane)ester DOI Creative Commons
Youwei Ma, Chihui Zheng, Gadi Slor

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(44)

Published: Aug. 6, 2024

Abstract The development of mechanically robust, chemically stable, and yet recyclable polymers represents an essential undertaking in the context advancing a circular economy for plastics. Here, we introduce novel cleavable β‐(1,3‐dioxane)ester ( DXE ) linkage, synthesized through catalyst‐free reaction β‐ketoester 1,3‐diol, to cross‐link poly(vinyl alcohol) PVA formation high‐performance thermosets with inherent chemical recyclability. , modified groups transesterification excess tert ‐butyl acetoacetate, undergoes cross‐linking reactions unmodified 1,3‐diols within itself upon thermal treatment. architecture improves ’s mechanical properties, Young's modulus toughness that can reach up 656 MPa 84 MJ cm −3 i.e. approximately 3‐ 12‐fold those linear respectively. Thermal treatment cross‐linked under acid conditions leads deconstruction networks, enabling excellent recovery (>90 %) . In absence either or acidic treatment, maintains its dimensional stability. We show is also possible when performed presence other plastics commonly found recycling mixtures. Furthermore, ‐based composites comprising carbon fibers activated charcoal by linkages are shown be fillers.

Language: Английский

Crosslinking of polyethylene with polysilsesquioxane via carbamate linkages: Synthesis, shape recovery, and reprocessing properties DOI
Jiawei Hu, Yuan Gao,

Guohua Hang

et al.

Journal of Polymer Science, Journal Year: 2024, Volume and Issue: 62(13), P. 2945 - 2960

Published: April 11, 2024

Abstract In this contribution, we reported the crosslinking of polyethylene (PE) with dynamic silyl ether bonds. First, polycyclooctene copolymers bearing hydroxyl groups were synthesized via ring‐opening metathesis copolymerization cyclooctene 5‐norbornene‐2‐methanol. The hydroxy‐functionalized further hydrogenated into corresponding PE copolymers. allowed to react 3‐isocyanatopropyltriethoxysilane obtain triethoxysilane groups. By taking advantage hydrolysis and condensation grafted onto chains, well crosslinked; polysilsesquioxane (PSSQ) segments behaved as linkages in networks. Notably, networks reprocessable (or recyclable) while zinc trifluoromethanesulfonate [Zn(OTf) 2 ] was incorporated. reprocessing properties quite dependent on densities. behavior is attributable introduction two chemistries: (i) bonds which catalyzed Zn(OTf) (ii) transcarbamoylation carbamates dibutyltin dilaurate. Owing crosslinking, displayed excellent shape memory properties. For networks, notably, original shapes can be reprogrammed aid exchange covalent introduced systems.

Language: Английский

Citations

4
Recycling of Polydicyclopentadiene Enabled with N‐Coordinated Boronic Ester Bonds DOI
Jiawei Hu, Yuan Gao,

Jianglu Teng

et al.

Macromolecular Rapid Communications, Journal Year: 2024, Volume and Issue: 45(16)

Published: May 9, 2024

In this contribution, the transformation of polydicyclopentadiene (PDCPD) from thermoset into vitrimer is introduced. First, two N-coordinated diboronic diols are successfully synthesized via reaction N,N,N-tri(2-hydroxyethyl)amine and/or N,N,N",N"-tetrakis(2-hydroxyethyl)ethylene diamine with 4-(hydroxymethyl) phenylboronic acid and then they transformed cyclic boronic diacrylates. The latter dienes carrying electron-withdrawing substituents used for ring opening insertion metathesis copolymerization (ROIMP) dicyclopentadiene to afford crosslinked PDCPD. PDCPD networks, ester bonds integrated. It found that as-obtained networks displayed excellent reprocessing properties. meantime, fracture toughness significantly improved. Owing inclusion bonds, modified PDCPDs have thermal stability much superior plain results reported in work demonstrate can be vitrimers introduction bonds.

Language: Английский

Citations

4
Is a Vitrimer with a High Glass Transition Temperature Available? A Case Study on Rigid Polyimides Cross‐Linked with Dynamic Ester Bonds DOI

Y. Y. Wang,

Du‐Yuan Hung,

Ying‐Ling Liu

et al.

Macromolecular Rapid Communications, Journal Year: 2024, Volume and Issue: unknown

Published: June 11, 2024

Abstract Vitrimers, possessing associative covalent adaptable networks, are cross‐linked polymers exhibiting malleable (glass‐like) feature and recyclable reprocessable (thermoplastics‐like) properties. The dynamic behaviors of vitrimer dependent on both chain/molecular mobility (glass transition temperature, T g ) bond‐exchanging reaction rate (topology freezing v ). This work aims probing the effect high stress relaxation physical recyclability vitrimers, employing a polyimide with ester bonds ( : 310 °C) as example. Due to its chain rigidity, does not exhibit extent behavior at 320 °C (10 above ), even though temperature is much higher than hypothetical . While raising processing 345 °C, exhibits time about 3300 s malleability. Nevertheless, side reactions may occur in recycling reprocessing process under harsh condition (high pressure) alter thermal properties recycled sample. diffusion control plays critical role topography having ceiling noticeable for developments vitrimers.

Language: Английский

Citations

4
Cleavable Strand‐Fusing Cross‐Linkers as Additives for Chemically Deconstructable Thermosets with Preserved Thermomechanical Properties DOI Creative Commons
Shu-yi Zhang, Zhenchuang Xu, Keith E. L. Husted

et al.

Angewandte Chemie International Edition, Journal Year: 2025, Volume and Issue: unknown

Published: March 27, 2025

Permanently cross-linked polymer networks-thermosets-are often difficult to chemically deconstruct. The installation of cleavable bonds into the strands thermosets using comonomers as additives can facilitate thermoset deconstruction without replacement permanent cross-links, but such monomers lead reduced thermomechanical properties and require high loadings function effectively, motivating design new optimal additives. Here, we introduce "strand-fusing cross-linkers" (SFCs), which fuse two network via a four-way cross-link. SFCs enable model polydicyclopentadiene (pDCPD) with little one-fifth molar loading needed achieve traditional comonomers. under oven curing well low-energy frontal ring-opening metathesis polymerization (FROMP) conditions improved properties, for example, glass transition temperatures, compared prior comonomer designs. This work motivates development increasingly compromising material performance.

Language: Английский

Citations

0
Cleavable Strand‐Fusing Cross‐Linkers as Additives for Chemically Deconstructable Thermosets with Preserved Thermomechanical Properties DOI Creative Commons
Shu-yi Zhang, Zhenchuang Xu, Keith E. L. Husted

et al.

Angewandte Chemie, Journal Year: 2025, Volume and Issue: unknown

Published: March 27, 2025

Abstract Permanently cross‐linked polymer networks—thermosets—are often difficult to chemically deconstruct. The installation of cleavable bonds into the strands thermosets using comonomers as additives can facilitate thermoset deconstruction without replacement permanent cross‐links, but such monomers lead reduced thermomechanical properties and require high loadings function effectively, motivating design new optimal additives. Here, we introduce “strand‐fusing cross‐linkers” (SFCs), which fuse two network via a four‐way cross‐link. SFCs enable model polydicyclopentadiene (pDCPD) with little one‐fifth molar loading needed achieve traditional comonomers. under oven curing well low‐energy frontal ring‐opening metathesis polymerization (FROMP) conditions improved properties, for example, glass transition temperatures, compared prior comonomer designs. This work motivates development increasingly compromising material performance.

Language: Английский

Citations

0
Networks of Polyurethane: Crosslinking via Sol-gel Process, Reprocessing with Silyl Ether Metathesis and Shape Recovery with Reconfigurability DOI
Yuan Gao,

Jianglu Teng,

Xibin Shen

et al.

Materials Today Communications, Journal Year: 2025, Volume and Issue: unknown, P. 112312 - 112312

Published: March 1, 2025

Language: Английский

Citations

0
Ultralow-Temperature-Resistant Poly(ethylfluorophenylsiloxane) Elastomers Synthesized by Postpolymerization Macromolecular Chain Exchange Reaction DOI
Linyu Li, Hang Zheng, Zhu Xia

et al.

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

Published: April 23, 2025

Language: Английский

Citations

0
Exclusive macrocyclization through multiple Si–O bond formations from diol and dichlorosilane DOI
Takahiro Iwamoto, Shiro Amano,

Kousuke Maeda

et al.

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

This paper describes an exceptionally efficient macrocyclization method through multiple Si–O bond formations between diol and dichlorosilane.

Language: Английский

Citations

0
Design of covalent adaptable networks with intrinsic flame retardancy DOI

Haoyuan Zu,

Zhishuai Geng,

Rongjie Yang

et al.

Polymer Bulletin, Journal Year: 2024, Volume and Issue: 81(12), P. 10489 - 10532

Published: March 29, 2024

Language: Английский

Citations

3
Circular Workflow for Thermosets: Activatable Repeat Unit Design for Regenerative Frontal Polymerization DOI
Zhenchuang Xu, Kecheng Wang, Benjamin A. Suslick

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 25, 2025

Thermoset materials are indispensable in high-performance applications due to their exceptional mechanical properties, chemical resistance, and thermal stability. However, cross-linked structure poses significant challenges for sustainable manufacturing end-of-life reprocessing. Herein, we present a novel approach regenerate polydicyclopentadiene (pDCPD) thermoset through one-pot deconstruction-reactivation strategy enabled by an "activatable repeat unit", norbornene-furan (NBF). The pendant furyl ring of NBF remains intact during the initial curing reaction via frontal ring-opening metathesis polymerization (FROMP) retains its reactivity subsequent Diels–Alder cycloaddition with situ generated benzyne. Deconstruction-reactivation proceeds one pot effectively recover activated oligomers further FROMP curing, thereby completing circular workflow. regenerated demonstrate retention key including glass transition temperature (Tg), stiffness, yield strength, while maintaining deconstruction capability. This provides framework material design regeneration, addressing critical circularity environmental impact.

Language: Английский

Citations

0