Dynamic Covalent Polymer Networks: A Molecular Platform for Designing Functions beyond Chemical Recycling and Self-Healing

Chemical Reviews, Год журнала: 2021, Номер 121(3), С. 1716 - 1745

Опубликована: Янв. 4, 2021

Dynamic covalent polymer networks (DCPN) have historically attracted attention for their unique roles in chemical recycling and self-healing, which are both relevant sustainable societal development. Efforts these directions intensified the past decade with notable progress newly discovered dynamic chemistry, fundamental material concepts, extension toward emerging applications including energy electronic devices. Beyond that, values of DCPN discovering/designing functional properties not offered by classical thermoplastic thermoset polymers recently gained traction. In particular, bond exchangeability has shown unparalleled design versatility various areas shape-shifting materials/devices, artificial muscles, microfabrication. Going beyond this basic exchangeability, molecular mechanisms to manipulate network topologies (topological transformation) led opportunities program polymers, concepts such as living topological isomerization. review, we provide an overview above particular focuses on strategies exploitation properties. Based this, point out remaining issues offer perspectives how class materials can shape future ways that complementary polymers.

Язык: Английский

---

Adaptable Crosslinks in Polymeric Materials: Resolving the Intersection of Thermoplastics and Thermosets

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(41), С. 16181 - 16196

Опубликована: Сен. 16, 2019

The classical division of polymeric materials into thermoplastics and thermosets based on covalent network structure often implies that these categories are distinct irreconcilable. Yet, the past two decades have seen extensive development bridge this gap through incorporation dynamic crosslinks, enabling them to behave as both robust networks moldable plastics. Although their potential utility is significant, growth adaptable (CANs) has obscured line between "thermoplastic" "thermoset" erected a conceptual barrier growing number new researchers entering discipline. This Perspective aims outline fundamental theory CANs provide critical assessment current status. We emphasize throughout unique properties emerge from chemistry, particularly highlight role crosslink exchange mechanism (i.e., dissociative or associative exchange) plays in resultant material under processing conditions. Predominant focus will be thermally induced behavior, majority presently employed chemistries rely thermal stimulus, it simple apply bulk materials. Lastly, identify issues address possible solutions for better understanding within field.

Язык: Английский

---

Vitrimers: Permanently crosslinked polymers with dynamic network topology

Progress in Polymer Science, Год журнала: 2020, Номер 104, С. 101233 - 101233

Опубликована: Март 15, 2020

Язык: Английский

---

Vitrimers: directing chemical reactivity to control material properties

Chemical Science, Год журнала: 2020, Номер 11(19), С. 4855 - 4870

Опубликована: Янв. 1, 2020

In this minireview, we survey recent advances in the development of vitrimer materials. Focus on how to chemically control their material properties is used highlight challenges for boosting potential emerging class polymer

Язык: Английский

---

Toward Stimuli‐Responsive Dynamic Thermosets through Continuous Development and Improvements in Covalent Adaptable Networks (CANs)

Advanced Materials, Год журнала: 2020, Номер 32(20)

Опубликована: Фев. 14, 2020

Abstract Covalent adaptable networks (CANs), unlike typical thermosets or other covalently crosslinked networks, possess a unique, often dormant ability to activate one more forms of stimuli‐responsive, dynamic covalent chemistries as means transition their behavior from that viscoelastic solid material with fluid‐like plastic flow. Upon application stimulus, such light irradiation, temperature, even distinct chemical signal, the CAN responds by transforming state temporal plasticity through activation either reversible addition bond exchange, which allows essentially re‐equilibrate an altered set conditions are those in original network is formed, simultaneously enabling new and shape, function, characteristics. As such, CANs span divide between thermoplastics, thus offering unprecedented possibilities for innovation polymer materials science. Without attempting comprehensively review literature, recent developments discussed here emphasis on most effective render these be stimuli responsive, features make broadly applicable.

Язык: Английский

---

Cleavable comonomers enable degradable, recyclable thermoset plastics

Nature, Год журнала: 2020, Номер 583(7817), С. 542 - 547

Опубликована: Июль 22, 2020

Язык: Английский

---

Reprocessable Cross-Linked Polymer Networks: Are Associative Exchange Mechanisms Desirable?

ACS Central Science, Год журнала: 2020, Номер 6(9), С. 1488 - 1496

Опубликована: Июль 29, 2020

Covalent adaptable networks (CANs) are covalently cross-linked polymers that may be reshaped via cross-linking and/or strand exchange at elevated temperatures. They represent an exciting and rapidly developing frontier in polymer science for their potential as stimuli-responsive materials to make traditionally nonrecyclable thermosets more sustainable. CANs whose cross-links undergo associative intermediates rather than dissociating separate reactive groups termed vitrimers. Vitrimers were postulated attractive subset of CANs, because cross-link mechanisms maintain the original density network throughout process. As a result, demonstrate gradual, Arrhenius-like reduction viscosity temperatures while maintaining mechanical integrity. In contrast, reprocessed by dissociation reformation have been exhibit rapid decrease with increasing temperature. Here, we survey stress relaxation behavior all dissociative which variable temperature or data reported date. All Arrhenius relationship between viscosity, only small percentage broken instantaneously under typical reprocessing conditions. such, show nearly identical over broad ranges typically used reprocessing. Given term vitrimer was coined highlight temperature, analogy vitreous glasses, discourage its continued use describe CANs. The realization mechanism does not greatly influence practical most suggests chemistries can considered fewer constraints, focusing instead on activation parameters, synthetic convenience, application-specific considerations.

Язык: Английский

---

Vitrimers: Current research trends and their emerging applications

Materials Today, Год журнала: 2021, Номер 51, С. 586 - 625

Опубликована: Июль 29, 2021

Язык: Английский

---

Malleable and Recyclable Thermosets: The Next Generation of Plastics

Matter, Год журнала: 2019, Номер 1(6), С. 1456 - 1493

Опубликована: Дек. 1, 2019

Язык: Английский

---

Catalyst-Free Vitrimers from Vinyl Polymers

Macromolecules, Год журнала: 2019, Номер 52(5), С. 2105 - 2111

Опубликована: Фев. 20, 2019

Cross-linked networks feature exceptional chemical and mechanical resilience but consequently lack recyclability. Vitrimers have emerged as a class of materials that the robustness thermosets recyclability thermoplastics without compromising network integrity. Most examples vitrimers involved new polymers with exchangeable bonds within their backbones. In pursuit more universal, commercially viable route, we propose method utilizing available inexpensive reagents to prepare from vinyl monomer-derived prepolymers contain cross-linkable β-ketoester functional groups. Controlled radical copolymerization methyl methracrylate (2-acetoacetoxy)ethyl methacrylate afforded linear were converted into in single step by treatment trifunctional amine. These displayed characteristic features reprocessability over many six (re)processing cycles. Critically, prepared through this process largely retain thermal properties counterparts, suggesting holds significant utility user-friendly relevant approach rational design diverse properties.

Язык: Английский

---