Structure–Reactivity–Property Relationships in Covalent Adaptable Networks

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(49), С. 22358 - 22377

Опубликована: Ноя. 29, 2022

Polymer networks built out of dynamic covalent bonds offer the potential to translate control and tunability chemical reactions macroscopic physical properties. Under conditions at which these occur, topology adaptable (CANs) can rearrange, meaning that they flow, self-heal, be remolded, respond stimuli. Materials with properties are necessary fields ranging from sustainability tissue engineering; thus time scale network rearrangement must compatible intended use. The mechanical CANs based on thermodynamics kinetics their constituent bonds. Therefore, strategies needed connect molecular worlds. In this Perspective, we analyze structure-reactivity-property relationships for several classes CANs, illustrating both general design principles predictive linear free energy (LFERs) applied CANs. We discuss opportunities in field develop quantitative open challenges.

Язык: Английский

---

Introducing Dynamic Bonds in Light‐based 3D Printing

Advanced Functional Materials, Год журнала: 2023, Номер 34(20)

Опубликована: Апрель 23, 2023

Abstract Light‐based 3D printing has received significant attention due to several advantages including high speed and resolution. Along with the development of new technologies, material design is key for next generation light‐based printing. Conventional printable polymeric materials, also known as photopolymers or photoresins, often lead thermosets–polymer networks cross‐linked by permanent covalent bonds which bring limited adaptability restricted reprocessability. Dynamic that can reversibly break reform enable network rearrangement, thereby offering unprecedented properties materials such adaptability, self‐healing, recycling capabilities. Hence, introducing dynamic into a promising strategy further expand meet diverse application scenarios printed multi‐functional moreover more demanding sustainable nature‐inspired considerations (e.g., self‐healing). Herein, an overview recent advances in printing, aiming bridge these two research fields presented. Importantly, current challenges are analyzed perspectives developing their potential applications provided.

Язык: Английский

---

High-Performance Recyclable and Malleable Epoxy Resin with Vanillin-Based Hyperbranched Epoxy Resin Containing Dual Dynamic Bonds

ACS Sustainable Chemistry & Engineering, Год журнала: 2023, Номер 11(30), С. 11077 - 11087

Опубликована: Июль 18, 2023

Dynamic covalent polymer networks represent new opportunities in the design of sustainable epoxy resins due to their excellent malleability and reprocessability; however, adaptable network is usually accompanied by low glass transition temperature, poor creep resistance, mechanical brittleness. Herein, we demonstrate a vanillin-based hyperbranched resin (VEHBP) containing disulfide imine dynamic bonds for recyclable malleable with high temperature (Tg), significantly improved properties. The 5%VEHBP exhibited 175 °C 130 34.1, 19.7, 173.3% increase tensile strength, storage modulus, toughness respectively, compared neat resin. Meanwhile, topological structure VEHBP complemented dual endowed these materials self-healing ability, reprocessability, degradability, which represents an important step toward fabrication high-performance networks.

Язык: Английский

---

Epoxy Adhesives with Reversible Hardeners: Controllable Thermal Debonding in Bulk and at Interfaces

Advanced Materials, Год журнала: 2023, Номер 35(31)

Опубликована: Май 18, 2023

Abstract On‐demand adhesive dismantling has the potential to improve multimaterial product recycling, but its implementation been hampered by a critical trade‐off between strong bonding and easy debonding. As result, temperature range in which these temporary adhesives can be used is relatively limited. Here, new class of dynamic epoxy resins reported that significantly extends this upper limit still achieves fast Specifically, two types polyamidoamine curing agents for hardening are developed, being polysuccinamides (PSA) polyglutaramides (PGA). debonding/rebonding process PSA especially PGA linkages more thermally demanding at same time robust than previously covalent systems, resulting materials triggered high temperatures, remain bonded over wide range. The versatility system demonstrated classical bulk formulations, as well linking PSA‐ or PGA‐functionalized surface. an attractive drop‐in strategy achieved producing debondable rebondable adhesives, with complementarity existing resin technologies applicable industrially relevant window.

Язык: Английский

---

Circularity in polymers: addressing performance and sustainability challenges using dynamic covalent chemistries

Chemical Science, Год журнала: 2023, Номер 14(20), С. 5243 - 5265

Опубликована: Янв. 1, 2023

This review provides a multidisciplinary overview of the challenges and opportunities for dynamic covalent chemistry-based macromolecules towards design new, sustainable, recyclable materials circular economy.

Язык: Английский

---

Mechanically Robust, Recyclable, and Self‐Healing Polyimine Networks

Advanced Science, Год журнала: 2023, Номер 10(19)

Опубликована: Апрель 23, 2023

To achieve energy saving and emission reduction goals, recyclable healable thermoset materials are highly attractive. Polymer copolymerization has been proven to be a critical strategy for preparing high-performance polymeric materials. However, it remains huge challenge develop Here, polyimine dynamic networks based on two monomers with bulky pendant groups, which not only displayed mechanical properties higher than the strong tough polymers, e.g., polycarbonate, but also excellent self-repairing capability recyclability as thermosets developed. Owing stability of conjugation effect by aromatic benzene rings, final far more stable reported counterparts, exhibiting hydrolysis resistance under both alkaline condition most organic solvents. These structure can completely depolymerized into recovery in an acidic aqueous solution at ambient temperature. Resulting from units, this method allows exchange reactions vitrimer easily within minutes self-healing function. Moreover, introduction trifluoromethyl diphenoxybenzene backbones significantly increases tensile This work provides effective fabricating polymer multiple functions.

Язык: Английский

---

Taking dynamic covalent chemistry out of the lab and into reprocessable industrial thermosets

Nature Reviews Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 31, 2025

Язык: Английский

---

Supramolecular Organic Nanofiller: A New Reinforcement Strategy for Dynamic Covalent Polymer Networks Toward Upcycling of Carbon Fiber Composites

Advanced Materials, Год журнала: 2025, Номер unknown

Опубликована: Янв. 22, 2025

Abstract Dynamic covalent polymer networks (DCPN) provide an important solution to the challenging recyclability of thermoset elastomers. However, dynamic bonds exhibit relatively weak bond energies, considerably decreasing mechanical properties DCPN. Herein, a novel reinforcement strategy for DCPN involving in situ formation supramolecular organic nanofillers through asynchronous polymerization is proposed. Owing difference reactivity isocyanate groups and gradual deblocking aldimine, cross‐linking hexamethylene diisocyanate isocyanate‐terminated prepolymer containing oxime–urethane with deblocked tris(2‐aminoethyl)amine facilitates transition from molecular interpenetration chains into immiscible polymerization. This results thermodynamic incompatibility between hyperbranched clusters long chains, inducing spontaneous nanofillers. Compared traditional strategies, improve Furthermore, interactions enable network excellent recyclability. The unique prepared allow their combination carbon fibers (CF) form CF composites outstanding personal‐protection applications, achieving composite upcycling. study offers on upcycling high‐performance composites.

Язык: Английский

---

Structure–Property Relationships of Elastomeric Vinylogous Urethane Thermosets and Their Application as Closed-Loop Recyclable Strain Sensors

Macromolecules, Год журнала: 2025, Номер 58(4), С. 1923 - 1934

Опубликована: Фев. 5, 2025

Developing closed-loop recyclable thermosets and understanding their structure–property relationships are essential steps in advancing a circular materials economy. Here, we present vinylogous urethane (VU) thermoset with recyclability, synthesized through the reaction of polytetrahydrofuran bisacetoacetate (aPTHF) tris(2-aminoethyl)amine (TREN). These VU polymers exhibit high elasticity, only 3–9% residual strain observed after cyclic tensile testing at maximum 100%, depending on molecular weight aPTHF network cross-link density. The two structural parameters also allow modulation mechanical stress-relaxation properties elastomers. To investigate hydrolysis linkages within hydrophobic matrix, employed heterogeneous system using biphasic mixture HCl CDCl3. Our findings show that VUs remain stable pure water but can be dissociated under acidic conditions, dissociation rate accelerated higher temperatures and/or presence concentrations. detailed investigations indicate potential elastomers as sustainable substrates for wearable sensors. We therefore conduct case study synthesizing sensor incorporation multiwalled carbon nanotubes (MCNs) into elastomer matrix. robustly detect various movements. Moreover, treatment both neat polymer composite diethyl ether solvent allows excellent recovery (>90%) TREN (86%), without discernible damage to MCNs reclaimed from latter.

Язык: Английский

---

Chemically Recyclable and Upcyclable Epoxy Resins Derived from Vanillin

ACS Sustainable Chemistry & Engineering, Год журнала: 2023, Номер 11(22), С. 8308 - 8316

Опубликована: Май 22, 2023

Epoxy resins constitute a very significant portion of all high-performance plastics due to their excellent thermal and mechanical properties that appear in wide range applications. Nevertheless, traditional epoxy networks show limitations regarding chemical recycling covalently crosslinked structures. The current methods recycle are not indeed through sustainable ways, but this issue could be solved by developing smart monomers with functional groups, which can switched between polymerized depolymerized states. Herein, we developed two bio-based liquid based on vanillin structures containing aldehyde, acetal, oxirane-ring functionalities. These were solvent-free conditions using commercially available diamines, resulting double-dynamic imine-acetal-containing thermosets. combine the systems dynamic polymers. Most importantly, such thermosets fully into vanillin, reused for preparation original monomers, mixture well-defined polyols, was upcycled polyurethane.

Язык: Английский

---