Poly(ionic liquid)s (PILs) are promising solid electrolytes because they simultaneously offer high ionic conductivity, chemical and electrochemical robustness, good mechanical strength, and facile processability. However, the covalent backbones of PILs preclude self-healing and closed-loop recycling, which increases their maintenance costs and environmental impact. Mimicking the reversible connectivity of neuronal synapses, this study introduces an ionic-liquid-based supramolecular polymer (ILSP) concept in which a multitopic ionic liquid is cross-linked through non-covalent interactions. Consequently, high ionic conductivity, spontaneous self-healing, and closed-loop recyclability are simultaneously achieved in a single solid electrolyte. As a proof-of-concept, dynamic Zr4+-COOH coordination between a carboxyl-terminated tetracationic ionic liquid and Zr4+ ions yields ILSP/Zr, a transparent and mechanically robust solid electrolyte that delivers an ionic conductivity of 1.29 × 10−2 mS cm−1 at 25 °C. Reversible metal-ligand interactions enable rapid damage healing even at −20 °C, and the ionic conductivity and healing efficiency of ILSP/Zr surpass those of reported lithium-salt-free self-healing PILs. Furthermore, acid-triggered depolymerization releases the ionic liquid monomer in a 90

High-performance, intrinsically sustainable plastics that simultaneously combine high strength, high modulus, toughness, and environmental stability remain elusive owing to the inherent trade-off between strength and toughness and the limited stability of noncovalent cross-links that enable recyclability. Here, we report a class of poly(urea-urethane) (PUU) plastics that reconcile these competing requirements through synergistic reinforcement by in situ-formed rigid hydrophobic nanodomains and bulky soft ionic cross-links. The incorporated bis(trifluoromethanesulfonyl)imide (TFSI-) anions increase interchain spacing and promote energy dissipation, while dynamically cross-linking cationic groups on PUU chains to compensate for the strength loss associated with increased free volume. The plastics exhibit a yield strength of 97.2 MPa, a Young's modulus of 2.02 GPa, and a toughness of 14.6 MJ m-3, while maintaining exceptional resistance to water, acidic, and alkaline aqueous solutions. The plastics are readily reprocessable and can serve as matrices for high-performance carbon-fiber composites, enabling facile and nondestructive carbon-fiber recovery.

Developing plastics that integrate biomass-derived components while achieving high mechanical strength and recyclability remains a formidable challenge. Here, we report chemically recyclable COPI plastics fabricated by reversibly cross-linking low-molecular-weight boronic acid-terminated polyimide (BPI) with vinyl-diol-functionalized castor oil (VCO) through dynamic boronic ester bonds. The resulting soft-rigid hybrid networks, reinforced by reversible boronic ester linkages, hydrogen bonding, and pi-pi stacking, exhibit exceptional performance, including a tensile strength of similar to 170.6 MPa, a Young's modulus of similar to 2.5 GPa, and a glass transition temperature of similar to 217.6 degrees C. Benefiting from reversible boronic esters, COPI plastics can be selectively depolymerized in DMAc/ethanol to recover high-purity BPI and biodegradable VCO. Integrating COPI with carbon fibers yields CF/COPI composites whose mechanical properties rival CF/epoxy thermosets while maintaining chemical recyclability. This work demonstrates an effective strategy for creating ultrastrong, processable, and recyclable plastics and composites by reversibly cross-linking rigid and flexible segments through well-designed dynamic chemistries.

Polymers that combine exceptional stretchability with high mechanical robustness are essential for advanced applications. To ensure their reliability, it is critical to integrate damage tolerance, which suppresses crack propagation and prevents catastrophic failure under extreme deformation. However, overcoming the intrinsic trade-off between stretchability and strength remains a formidable challenge in polymer science, particularly when damage tolerance is also required. Here, we show the scalable fabrication of super-stretchable polymers exhibiting exceptional mechanical robustness and remarkable damage tolerance, achieved by cross-linking soft polymer chains through synergistic urea-based hydrogen bonding and hydrophobic interactions. These polymers exhibit record-high elongations up to ∼100,000 times their original length while maintaining an extensional true stress of 35.0 MPa at a strain of 33.6, and an extraordinary fracture energy exceeding 374.8 kJ m-2. The extreme stretchability of these polymers arises from the successive breakage, chain slippage, and reformation of noncovalent cross-links. Meanwhile, mechanical robustness and pronounced strain hardening are sustained by a strain-induced transition of urea hydrogen bonds from double to quadruple configurations, together with the progressive orientation of polymer chains. These reversibly cross-linked polymers, featuring intrinsic self-healing and reprocessability, open broad opportunities for extremely deformable polymer materials where robustness, reliability, and sustainability are paramount.

Achieving elastomers that simultaneously combine ultrahigh strength, high modulus, and excellent elasticity remains a longstanding challenge because these properties are intrinsically conflicting. Here, we report a dual phase-separated nanodomain strategy that resolves this trade-off by transforming reversible cross-links into spatially confined reinforcing nanodomains. Elastomers are fabricated via copolymerization of rigid aromatic polyurea segments with flexible poly(urethane-urea) chains containing acylsemicarbazide moieties. The resulting elastomers exhibit an exceptional combination of mechanical properties, including tensile strength of 104.6 MPa, Young's modulus of 43.1 MPa, toughness of 350 MJ m-3, and full recovery after 600% strain. Small-angle x-ray scattering and electron microscopy reveal two distinct nanodomains originating from self-assembled aromatic polyurea segments and acylsemicarbazide-stacked hydrogen-bond arrays, respectively. Their synergistic reinforcement increases matrix rigidity while preserving entropy elasticity, enabling the simultaneous realization of ultrahigh mechanical robustness and excellent elastic recovery. The elastomers further demonstrate outstanding puncture resistance, environmental stability, healability, and reprocessability. When used as binders for carbon-fiber fabrics, the composites achieve record-high fracture energies of up to 2059 kJ m-2, owing to the exceptional mechanical robustness and energy dissipation of the elastomer, together with strong elastomer-fiber interfacial adhesion. This dual nanodomain design provides a novel route to high-performance elastomers that transcend conventional strength-modulus-elasticity trade-offs.

Low hysteresis, superior toughness, and high mechanical strength are essential for enhancing the reliability and durability of stretchable ionic conductors. However, the production of ionic conductors with these mutually exclusive properties remains a great challenge. Herein, low-hysteresis and highly resilient liquid-free ionic conductors with a high strength of similar to 4.0 MPa and a high toughness of similar to 19.6 MJ/m3 are fabricated by complexation of vanillin-grafted polyvinyl alcohol (VPVA) and solid-state ionic liquid (IL), followed by being crosslinked through 1,1'-ferrocenedicarboxaldehyde (FcDa) with the force-dependent conformational change characteristic (denoted as V-I-F). During small mechanical loading (<= 200% strain), FcDa serve as rigid crosslinkers to efficiently suppress energy dissipation of the V-I-F ionic conductors, resulting in conductors with low hysteresis. Upon large mechanical loading, ferrocene in FcDa significantly deforms to activate sufficient energy dissipation pathways, which dramatically improve the toughness and damage resistance of ionic conductors. Even after being crushed by a 1.5-ton car for 20 times, the V-I-F ionic conductors can still immediately recover to their original shape without damage and IL leakage. Meanwhile, the V-I-F ionic conductors show extremely low-hysteresis properties in electrical response aspect and display highly stable and reproducible sensing performances over 4500 uninterrupted loading-unloading cycles at a 200% strain.

Triboelectric nanogenerators (TENGs) are promising candidates for flexible, self-powered, and highly sensitive pressure sensors in advanced robotics and wearable electronics. However, their practical deployment in complex environments is hindered by humidity, contamination, strain, and mechanical/chemical damage-induced output issues (i.e., attenuation, crosstalk, and even complete failure). Herein, the first TENGs engineered to simultaneously withstand all four hazards, denoted I-4-TENGs, are introduced. This breakthrough is enabled by a room-temperature self-healing omniphobic slippery (RSOS) elastomer that integrates sextuple hydrogen bonds for mechanical strength, pendant perfluoroundecyl chains for omniphobic slipperiness and a high dielectric constant, and 1-hexyl-3-methylimidazolium chloride for room-temperature self-healing capabilities. With the RSOS elastomer as the triboelectric layer and eutectic gallium-indium as the electrode, the I-4-TENGs deliver good sensing performance, excellent mechanical robustness, and a record-high output power density among self-healing TENGs. Remarkably, they retain >99% of their output voltage under extreme conditions such as 90% relative humidity, exposure to diverse contaminants, 500% tensile strain, and repeated mechanical/chemical damage. Moreover, I-4-TENG arrays enable stable, spatially resolved impact detection even after stretching, oil rinsing, or complete severing. This work establishes a new paradigm for resilient, self-powered pressure sensing systems capable of operating reliably in harsh, real-world environments.

High-performance engineering plastics exhibit outstanding mechanical robustness and chemical stability, yet their robust structures often hinder chemical recyclability. Here we report a monomer conversion strategy that enables chemical recycling of high-strength and chemically stable plastics without monomer separation. The plastics are constructed by reversibly cross-linking an amino-terminated poly(aryl ether ketone) macromonomer (PAEK) with its aldehyde-functionalized derivative (PA2EK) through dynamic imine bonds, affording reversibly cross-linked PAEK (rPAEK) networks. The resulting rPAEK plastics exhibit a tensile strength of ∼85.8 MPa, a Young's modulus of ∼2.04 GPa, and a high glass transition temperature (Tg) of ∼171 °C, with mechanical and thermal properties comparable to those of conventional PAEK. Notably, the imine bonds are confined within hydrophobic and rigid aromatic environments formed by densely packed polymer chains, which effectively suppresses bond dissociation under ambient conditions and endows rPAEK with excellent chemical stability. Chemical recycling of rPAEK proceeds through cleavage of the dynamic imine bonds to generate PAEK and PA2EK, followed by conversion of PA2EK back to PAEK via amide hydrolysis, enabling recovery of a single macromonomer without monomer separation. Integration of rPAEK with carbon fibers (CFs) further affords chemically recyclable CF-rPAEK composites with mechanical properties comparable to those of epoxy-based CF-reinforced composites.

Fully recyclable all-solid-state supercapacitors (ASSCs) that are highly stretchable and self-healable are ideal for next-generation wearable electronics but remain underexplored. Here, a fully recyclable ASSC is developed by integrating elastic electrodes and solid-state electrolytes derived from reversibly cross-linked polymers. The elastic electrodes, composed of polyurethane (PU) elastomers and MXene-carbon nanotube (MX-CNT) hybrids (denoted as PU/MX-CNT), exhibit high stretchability, conductivity, and mechanical robustness. The solid-state hydrogel electrolyte, composed of KCl-loaded polyvinyl alcohol (PVA) derivatives cross-linked by reversible borate ester bonds, exhibits strong interfacial adhesion with PU/MX-CNT electrodes. The resulting ASSCs, fabricated by sandwiching the PVA electrolyte between two PU/MX-CNT electrodes, deliver a high areal capacitance of 643 mF cm-2 and a Coulombic efficiency of 89.8%. They also exhibit excellent mechanical and electrochemical stability, retaining 96.1% of original capacitance after 12 000 charge-discharge cycles and 91.7% after 1200 stretching cycles at 100% strain. Notably, the ASSCs demonstrate rapid self-healing at room temperature and can be fully disassembled in selective solvents to recover PU, MX-CNT, and PVA electrolytes with high yields and purities. The refabricated ASSCs exhibit electrochemical performance nearly identical to the pristine devices. This work presents a practically useful strategy for fabricating high-performance, recyclable ASSCs, advancing the development of sustainable energy storage.

Achieving outstanding water resistance in reversibly cross-linked elastomers (RCEs) remains challenging due to the presence of polar and hydrophilic groups within polymer chains. In this study, we present the fabrication of mechanically robust, healable, and recyclable RCEs with exceptional water resistance by incorporating hydrophobic hierarchical supramolecular interactions into poly(tetramethylene ether glycol) (PTMEG)-based polyurethane elastomers. These hierarchical supramolecular interactions, consisting of hydrogen bonding and π-π stacking, exhibit high binding energy, facilitating the in situ formation of phase-separated hydrophobic nanostructures that significantly enhance the water resistance of the elastomers. Consequently, the elastomers exhibit outstanding water resistance, with a water absorption as low as 1.1 wt % even after 40 days of immersion in water. In addition to their superior water resistance, the elastomers exhibit excellent mechanical properties, including a tensile strength of ∼67.8 MPa, toughness of ∼633 MJ m-3, and fracture energy of ∼160 kJ m-2. These mechanical properties are attributed to the synergistic effects of phase-separated nanostructures and strain-induced crystallization of PTMEG segments. Furthermore, the reversibility of the hydrophobic hierarchical supramolecular interactions enables the convenient healing and recycling of the elastomers, allowing the healed and recycled elastomers to restore their original mechanical performance. These elastomers were further demonstrated to be effective in encapsulating flexible electrochromic devices for underwater applications.

Current thermochromic materials for smart windows suffer from poor environmental stability, lack of self-healing and recyclability, and susceptibility to contamination. In this study, thermochromic supramolecular ionogels with excellent environmental stability, efficient room-temperature self-healing and recyclability properties, as well as amphiphobic slippery surfaces, are fabricated by incorporating binary ionic liquids into a rationally designed self-healing polyurethane with perfluoroalkyl side chains. The outstanding and stable thermochromic performance of the resulting ionogels stems from the hydrogen bondmediated, confined, and reversible phase separation of ionic liquids within the polyurethane network, enabling the ionogels to effectively reduce indoor temperatures and enhance the comfort of occupants. The surface-enriched perfluoroalkyl side chains enable various liquids, including water, alkanes, and edible oils, to easily slide off the ionogel surface without leaving any residue, preventing the transmittance decrease and thermochromic performance degradation caused by contaminations. The dynamic hydrogen bonds within the polyurethane network enable the ionogels to repeatedly heal physical and chemical damages, as well as to be recycled multiple times without performance loss, thereby reducing maintenance costs and minimizing material waste. This study provides a novel approach to developing advanced thermochromic materials for smart windows, potentially improving the building energy efficiency and sustainability.

Developing chemically recyclable polymers that offer ultrahigh mechanical strength, exceptional chemical stability, mild recycling conditions, and scalability for mass production remains a significant challenge. This study presents a novel class of chemically recyclable plastics, synthesized at kilogram scale in the laboratory, by reversibly cross-linking aromatic polyamide macromonomers with boroxines, imine bonds, and hydrogen bonds. These plastics, denoted as PA-B3O3, exhibit an impressive tensile strength of 142.1 MPa, a Young's modulus of 2.39 GPa, a glass transition temperature of ∼211.6 °C, and outstanding chemical resistance to acidic/basic aqueous solutions and organic solvents. PA-B3O3 plastics can be depolymerized in a mixed solvent of N,N-dimethylacetamide and aqueous HCl solution, allowing for efficient recovery of the original amino-terminated polyamide (PA-NH2) via precipitation in selective solvents, even when mixed with polymer waste streams. This study represents a significant advancement toward the practical application of mechanically robust, chemically resistant, and recyclable polymers.

Today, energy is essential for every aspect of human life, including clothing, food, housing and transportation. However, traditional energy resources are insufficient to meet our modern needs. Self-powered sensing devices emerge as promising alternatives, offering sustained operation without relying on external power sources. Leveraging advancements in materials and manufacturing research, these devices can autonomously harvest energy from various sources. In this review, we focus on the current landscape of self-powered wearable sensors, providing a concise overview of energy harvesting technologies, conversion mechanisms, structural or material innovations, and energy storage platforms. Then, we present experimental advances in different energy sources, showing their underlying mechanisms, and the potential for energy acquisition. Furthermore, we discuss the applications of self-powered flexible sensors in diverse fields such as medicine, sports, and food. Despite significant progress in this field, widespread commercialization will necessitate enhanced sensor detection abilities, improved design factors for adaptable devices, and a balance between sensitivity and standardization.

Efficient recycling of carbon fiber‐reinforced polymer composites (CFRCs) into their original monomers and carbon fibers (CFs) in a non‐destructive manner remains a significant challenge. In this study, high‐performance, closed‐loop recyclable aromatic polyamide (APAD) plastics are synthesized via polycondensation of aromatic amines and aromatic aldehydes through dynamic imine bonds. Due to their fully aromatic structure as well as interchain hydrogen bonds and π–π interactions, APAD plastics exhibit a tensile strength of ≈78.3 MPa, a glass transition temperature ( T g ) of ≈200.4 °C, and excellent chemical resistance. The APAD plastics can be depolymerized in a mixture of polar organic solvents and acids at ambient temperature, enabling high‐purity recovery of monomers through their precipitation in selective solvents. Water‐resistant CF/APAD composites are fabricated through complexation of APAD plastics with CF cloths. These composites exhibit mechanical properties comparable to those of CF/epoxy thermoset composites and superior thermal stability. The mild depolymerization conditions for APAD plastics enable the efficient disintegration of CF/APAD composites. Therefore, non‐destructive recovery of CFs and monomers can be realized. The recovered CF cloths and monomers can be used to re‐manufacture the original CF/APAD composites. This study presents an effective method for the closed‐loop recycling of CFRCs, offering significant environmental and economic benefits.

There is increasing demand for self‐healing high‐temperature proton exchange membranes (HT‐PEMs) with superior mechanical robustness and proton conductivity. In this study, the fabrication of mechanically robust HT‐PEMs (denoted as N‐IL‐PW) is demonstrated by integrating high proton conductivity and the ability to in situ heal fatigue and damage during operation via the complexation of Nafion, phosphotungstic acid (PW) clusters, and ionic liquids (ILs). Originating from the synergistic effect of high‐density electrostatic interactions as well as hydrogen bonds in ionic domains and stable crystalline domains, the N‐IL‐PW membranes are highly resilient and fatigue resistant, and display excellent creep resistance even at 170 °C. Under an anhydrous condition of ≈170 °C, the N‐IL‐PW membranes have a high proton conductivity of ≈18.86 mS cm −1 . Meanwhile, the hydrogen‐powered HT‐PEM fuel cells assembled with N‐IL‐PW membranes exhibit good cell performance under an anhydrous condition of ≈120 °C. More importantly, the reversibility of electrostatic and hydrogen bonding interactions enables the membranes in situ to heal fatigue and mechanical damages under fuel cell operation conditions. Healed membranes can regain their pristine mechanical properties, proton conductivity, hydrogen barrier property, and cell performance. Excellent high‐temperature creep resistance, fatigue resistance, and healing capability can work in concert to enhance the reliability of N‐IL‐PW membranes.

There is a significant need for elastomers that retain their elastic characteristics and mechanical robustness at temperatures ranging from extremely low to extremely high. However, low- and high-temperature resistances are mutually exclusive. Here, a mechanically robust elastomer that integrates low-temperature resistance and high-temperature resistance is fabricated using a multiblock polymer of polybutadiene (PB)/polyimide (PI). The elastomer exhibits an ultralow glass transition temperature of -82 degrees C and retains its elastic characteristics from -60 to 90 degrees C. The elastomer has a flexible-rigid binary complementary network, in which the PI segments with a highly conjugated structure and significant aromaticity aggregate to form phase-separated nanodomains to cross-link flexible PB segments. Serving as nanofillers, nanodomains strengthen the elastomer and significantly enhance its high-temperature resistance. Furthermore, the nanodomains prevent the crystallization of PB segments and thus ensure their high flexibility at low temperatures. The mechanical properties of the elastomer under cold, normal, and elevated temperatures exceed those of general-purpose rubbers and previously reported low-temperature elastomers. Moreover, the elastomer is highly stable in acidic and basic aqueous solutions. This elastomer holds particular promise as a tire tread compound because it provides excellent winter traction and ultralow rolling resistance.

The application of self‐healing superhydrophobic triboelectric nanogenerators (TENGs) is currently limited by their poor wear resistance, which stems from their reliance on nano/microscale hierarchical structures. Drawing inspiration from corals, this study presents the development of ultra‐wear‐resistant superhydrophobic TENGs with sub‐zero temperature self‐healing capability (USSS‐TENGs) by incorporating rationally designed hydrophobic self‐healing polyurethane (SFPU) and poly(vinylidene fluoride) nanoparticles (PVDF NPs) into iron foams. The rigid protruding structures of the iron foams protect the incorporated superhydrophobic SFPU–PVDF NPs composites by preferentially making contact with and bearing stress from foreign objects. This innovative design enables the USSS‐TENGs to maintain their superhydrophobicity after repeated sandpaper abrasion, knife scratching, and even car transit, demonstrating a superior wear resistance compared to other superhydrophobic materials. Furthermore, driven by free energy minimization, the migration of SFPU to damaged areas enables the USSS‐TENGs to self‐heal their superhydrophobicity at −30 °C, underwater, and in vacuum. Owing to their outstanding wear resistance and self‐healing superhydrophobicity, the USSS‐TENGs show great application potential as smart roofs and floor tiles, capable of providing stable and durable electricity generation from processes such as precipitation, human walking/jumping, and vehicle movement. This capability has not been previously reported for superhydrophobic TENGs, irrespective of their self‐healing properties.

The current application of self-healing solid omniphobic slippery coatings is severely constrained by the elevated temperature requirements for their self-healing mechanisms. This work presents the first room-temperature self-healing solid omniphobic slippery coating with exceptional transparency and robust liquid repellency across a wide range of surface tensions. This breakthrough is accomplished by incorporating a minute quantity of 1-hexyl-3-methylimidazolium chloride ([Hmim]Cl) into a rationally engineered amorphous polyurethane comprising perfluoroalkyl side chains. In-depth studies reveal that, unlike other ionic liquids, the synergistic formation of hydrogen bonds between the anions and cations of [Hmim]Cl and the hard segments of the polyurethane uniquely diminishes the size of the hard phase domains and enhances their dynamics within the coating. This endows the coating with the capability to spontaneously, efficiently, and repeatedly heal both mechanical and chemical damage through the migration of polymer chains to the sites of injury at ambient temperature. To highlight its practical applicability, this coating is utilized to fabricate a transparent triboelectric nanogenerator (TENG). Compared to conventional TENGs, the proposed TENG not only exhibits superior antifouling and self-cleaning capabilities but also demonstrates an unparalleled capacity to convert the dripping of alkanes, edible oils, polyols, and water into electric energy.

To address the growing demands of modern society for polymer materials with high mechanical performance and stability,it is imperative to develop sustainable polymers that combine dynamic functionalities with properties comparable to or exceeding those of traditional polymers.Here,we propose a new concept of reversibly crosslinked polymers(RCPs).RCPs are three-dimensional polymer networks in which polymer chains are reversibly crosslinked through noncovalent interactions and/or dynamic covalent bonds.By constructing RCPs from polymeric building blocks,the fraction of stable covalent bonds relative to reversible interactions is increased,thereby ensuring satisfactory strength and stability.This feature article comprehensively summarizes our advances in designing and fabricating high-performance RCPs.Using a layer-by-layer assembly strategy,we fabricated a series of self-healing/healable RCP films and elucidated their healing mechanisms.Inspired by this method,we further developed an efficient solution-based polymer complexation approach to produce bulk RCPs,extending healability from films to plastics,elastomers,and hydrogels/ionogels.Moreover,we demonstrate that high-performance RCPs can be achieved by combining multiple types of reversible interactions with reinforcement from carefully engineered in situ-formed phase-separated nanostructures.By tailoring the rigidity,deformability,and dynamic dissociability of these nanostructures,we obtained RCPs with strengths comparable to or exceeding those of conventional polymers,as well as materials with unique mechanical properties rarely achieved in traditional systems,such as high-strength,low-hysteresis hydrogels/ionogels,damage-resistant elastomers,and ultra-tough plastics with superior low-temperature impact resistance.Importantly,the dynamic nature of the crosslinking network imparts excellent healing,reprocessing,and recycling capabilities to these RCPs.We believe that RCPs open a new avenue for the development of high-performance sustainable polymers.