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Stretching or compression can induce significant energetic, geometric, and spectroscopic changes in materials. To fully exploit these effects in the design of mechano- or piezo-chromic materials, self-healing polymers, and other mechanoresponsive devices, a detailed knowledge about the distribution of mechanical strain in the material is essential. Within the past decade, Judgement of Energy DIstribution (JEDI) analysis has emerged as a useful tool for this purpose. Based on the harmonic approximation, the strain energy in each bond length, bond angle, and dihedral angle of the deformed system is calculated using quantum chemical methods. This allows the identification of the force-bearing scaffold of the system, leading to an understanding of mechanochemical processes at the most fundamental level. Here, we present a publicly available code that generalizes the JEDI analysis, which has previously only been available for isolated molecules. Now, the code has been extended to two- and three-dimensional periodic systems, supramolecular clusters, and substructures of chemical systems under various types of deformation. Due to the implementation of JEDI into the Atomic Simulation Environment, the JEDI analysis can be interfaced with a plethora of program packages that allow the calculation of electronic energies for molecular systems and systems with periodic boundary conditions. The automated generation of a color-coded three-dimensional structure via the Visual Molecular Dynamics program allows insightful visual analyses of the force-bearing scaffold of the strained system. [ABSTRACT FROM AUTHOR]

[Display omitted] Traditional kinesiology tape (KT) is an elastic fabric tape that clinicians and sports trainers widely use for managing ankle sprains. However, inadequate mechanical properties, adhesive strength, water resistance, and micro-damage generation could affect the longevity of the tape on the skin during physical activity and sweating. Therefore, autonomous room-temperature self-healing elastomers with robust mechanical properties and adequate adhesion to the skin are highly desirable to replace traditional KT. Ionic aggregates were introduced into the polymer matrix via electrostatic attraction between polymer colloid and polyelectrolyte to achieve such elastic tape. These ionic aggregates act as physical crosslink points to enhance mechanical properties and dissociate at room temperature to provide self-healing functions. The obtained elastic tape possesses a tensile strength of 3.7 MPa, elongation of 940 %, toughness of 16.6 MJ∙m−3, and self-healing efficiency of 90 % for 2 h at room temperature. It also exhibits adequate reversible adhesion on the skin via van der Waals force and electrostatic interaction in both dry and wet conditions. The new elastic tapes have great potential in biomedical engineering for preventing and rehabilitating ankle sprain. [ABSTRACT FROM AUTHOR]

[Display omitted] Flexible electronics have introduced new challenges for efficient human–machine interactions. Hydrogels have emerged as prominent materials for electronic wearable applications due to their exceptional mechanical deformability and lightweight characteristics combined in some cases with conductive properties, and softness. Additionally, bio-interphases require multisensory response to stress, strain, temperature, and self-healing capacity. To mimic these properties, this work developed interpenetrated hydrogel networks composed of chitosan (CHI) and polyacrylic acid (PAA), combined with Fe (III) ions and varying amounts of NMBA (0–0.25 %), to achieve tailored conductivity (0.8–2.5 mS/cm), self-healing, self-standing and mechanical properties (E = 11.7–110 Pa and fracture strain = 64.9–1923 %) suitable for strain sensor applications. The results revealed a significant influence of the restrictive effect on the mobility of uncrosslinked chain segments, caused by Fe ions and NMBA, on the piezoresistance (GF 2.1–1.3) and self-healing capability of the gels. Interestingly, a transparent/turbid transition, driven by microphase separation that is characteristic of systems with high dynamic interactions, was encountered for the first time in these hydrogels. This transition was analyzed in relation to external temperature, water content, pH, and the influence of Fe ions and NMBA. The simultaneous sensitivity of these materials to temperature and pH, along with their piezoresistive and self-healing behaviour, can be highly valuable for multifunctional sensors in a wide range of applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Thermoset epoxy resin-based materials are widely used, but their permanent cross-linked network limits their processability and reusability, which can lead to environmental burdens. In this work, by exploiting the weak reactivity of aniline to design appropriate reaction ratios, we achieved a linear link between the epoxy resin and the curing agent. This linear link, along with the crosslinking points provided by the flexibly branched polyurethanes, avoids the inherent brittleness associated with the highly crosslinked network of conventional epoxy resins. As a result, the adhesive exhibits extraordinary improvements in extensibility and toughness. The lap shear strength, tensile strength and elongation at break reach 11.9 MPa, 14.4 MPa and 607 %, respectively. The fracture toughness is as high as 109.6 kJ/m2, far beyond the existing epoxy adhesives. The synergistic effect of disulfide bonds and hydrogen bonds confers the adhesive with self-healing and repeatable bonding characteristics. The multi-level hydrogen bonding and appropriate phase separation structure are key to optimizing toughness, resulting in excellent comprehensive performance. The introduction of polyurethane not only improves toughness but also enhances the interfacial bonding force between the adhesive and the substrate, broadening the scope of applications. The prepared high-performance polymers provide new insights into reusable epoxy adhesives. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: Self-driven actions, like motion, are fundamental characteristics of life. Today, intense research focuses on the kinetics of droplet motion. Quantifying macroscopic motion and exploring the underlying mechanisms are crucial in self-structuring and self-healing materials, advancements in soft robotics, innovations in self-cleaning environmental processes, and progress within the pharmaceutical industry. Usually, the driving forces inducing macroscopic motion act at the molecular scale, making their real-time and high-resolution investigation challenging. Label-free surface sensitive measurements with high lateral resolution could in situ measure both molecular-scale interactions and microscopic motion. Experiments: We employ surface-sensitive label-free sensors to investigate the kinetic changes in a self-assembled monolayer of the trimethyl(octadecyl)azanium chloride surfactant on a substrate surface during the self-propelled motion of nitrobenzene droplets. The adsorption–desorption of the surfactant at various concentrations, its removal due to the moving organic droplet, and rebuilding mechanisms at droplet-visited areas are all investigated with excellent time, spatial, and surface mass density resolution. Findings: We discovered concentration dependent velocity fluctuations, estimated the adsorbed amount of surfactant molecules, and revealed multilayer coverage at high concentrations. The desorption rate of surfactant (18.4 s−1) during the microscopic motion of oil droplets was determined by in situ differentiating between droplet visited and non-visited areas. [ABSTRACT FROM AUTHOR]

This study developed UV‐responsive microcapsules to enhance the self‐healing properties of asphalt, addressing the limitations of low survival rates and single‐release mechanisms in current encapsulated rejuvenators. The microcapsules, featuring a urea‐formaldehyde shell embedded with polydopamine‐coated black phosphorus nanosheets (BP/DA) and microalgae bio‐oil as the core, can convert solar energy into thermal energy, promoting proactive self‐healing in asphalt materials. BP/DA expands the microcapsules' light absorption range, enhancing their photothermal conversion efficiency. When incorporated into styrene‐butadiene‐styrene (SBS)‐modified asphalt at a 1.5% dosage, the microcapsules (BP/DA/MC) improved the mechanical properties: ductility increased by 13.7%, softening point rose by 2%, and penetration decreased by 3.3%. The storage modulus (G′) at 46 and 64°C increased by 35.9% and 24.3%, respectively, compared to SBS asphalt. Additionally, the ductility self‐healing rate of BP/DA/MC/SBS asphalt improved by 209.7%, with a healing index (HI) of 78.16%. The microcapsules also demonstrated excellent photothermal conversion, increasing the asphalt's temperature by 22.6% under identical lighting conditions. This research offers a new method for developing intelligent self‐healing asphalt with multi‐mechanism activation, providing theoretical support for future third‐generation microcapsule‐based asphalt with remote‐controlled release and activation response. [ABSTRACT FROM AUTHOR]

Highlights Self‐healing technology based on micro/nano‐encapsulated materials has shown great potential in extending material lifespan, preventing performance degradation, and reducing maintenance costs. In this study, a novel mechanically responsive microcapsule is successfully prepared by in‐situ polymerization, which can be used for self‐healing of polymer composites. The core‐shell microstructure is characterized, and its stability and potential self‐healing ability is verified. The microcapsule is introduced into polymer matrix, and the epoxy fingerprint region at the preseted defect location is monitored in real‐time under stress stimulus using infrared spectroscopy, revealing the process from microcapsules rupture to liquid core materials releasing and self‐healing mechanism. Tensile tests are conducted to explore the effect of microcapsule fillers on the mechanical properties of polymer composites. The optimal microcapsule content is determined based on the comprehensive evaluations of self‐healing performance. The core‐shell microcapsules provide excellent in‐situ real‐time self‐healing capability for composite matrix damage during load‐bearing. The self‐healing under stress stimulus can better guarantee the reliability of polymer composites in service. A novel stress responsive microcapsule is prepared for polymer self‐healing. Stability and self‐healing ability of core‐shell microcapsule is verified. Preseted defect is in situ real‐time detected to reveal self‐healing mechanism. Effect of microcapsule content on composite mechanical properties is explored. Self‐healing better guarantee the reliability of polymer composites in service. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to develop a polymer cement-based waterproof coating with self-healing capability to efficiently and intelligently solve the building leakage caused by cracking of waterproof materials, along with excellent durability to prolong its service life. Design/methodology/approach: Ion chelators are introduced into the composite system based on ethylene vinyl acetate copolymer emulsion and ordinary Portland cement to prepare self-healing polymer cement-based waterproof coating. Hydration, microstructure, wettability, mechanical properties, durability, self-healing performance and self-healing products of polymer cement-based waterproof coating with ion chelator are investigated systematically. Meanwhile, the chemical composition of self-healing products in the crack was examined. Findings: The results showed that ion chelators could motivate the hydration of C2S and C3S, as well as the formation of hydration products (C-S-H gel) of the waterproof coating to improve its compactness. Compared with the control group, the waterproof coating with ion chelator had more excellent water resistance, alkali resistance, thermal and UV aging resistance. When the dosage of ion chelator was 2%, after 28 days of curing, cracks with a width of 0.29 mm in waterproof coating could fully heal and cracks with a width of 0.50 mm could achieve a self-healing efficiency of 72%. Furthermore, the results reveal that the self-healing product in the crack was calcite crystalline CaCO3. Originality/value: A novel ion chelator was introduced into the composite coating system to endow it with excellent self-healing ability to prolong its service life. It has huge application potential in the field of building waterproofing. [ABSTRACT FROM AUTHOR]

Geopolymers are the result of the reaction of alkaline activators with reactive aluminosilicates. By dissolving these aluminosilicates and undergoing processes of polycondensation and geopolymerization, they form robust structures with distinct properties compared to other ceramics. These non-crystalline materials exhibit notable resistance to corrosion, heat, and environmental conditions, such as changes in pressure and temperature. Consequently, geopolymers, e.g., of stoichiometric composition (M 2 O•Al 2 O 3 •4SiO 2 •11H 2 O (or 13H 2 O)), find a place between cement and ceramics regarding mechanical properties. Considering the formulation of geopolymer blends, this study demonstrates that these materials have self-healing and self-glazing properties under high-temperature conditions. Through systematic experimentation and considering the specific properties of sodium-based (Na-GP) and potassium-based (K-GP) geopolymers, a combination of sodium and potassium waterglass compounds with different weight percentages were used to achieve geopolymer materials with optimum self-healing and self-glazing properties. Moreover, these samples were subjected to heat treatment under various time and temperature conditions to optimize their properties in terms of crystallization, and the best results were reported from among these variables. Based on the findings, the specific combination consisting of 75 wt% sodium waterglass and 25 wt% potassium waterglass were the best mixtures. This mixture was heated at a rate of 5 °C per minute to a temperature of 1000 °C and held isothermally for 6 h before being cooled at the same rate. As a result, an amorphous geopolymer turned into a ceramic with irreversible, self-healing, and self-glazing capabilities. [ABSTRACT FROM AUTHOR]

The article discusses the long-term development of mechanical properties of concrete with varying water to cement ratios and internal curing ability. It explores the impact of water to cement ratios on autogenous shrinkage and microcrack formation in high-performance concrete. The study measures compressive and bending strengths of concrete mixtures with different curing methods and internal curing using porous aggregates. Additionally, it evaluates frost resistance and the effectiveness of internal curing in enhancing mechanical properties and frost resistance of concrete. The research aims to provide insights into sustainable concrete development and the potential of internal curing for improving concrete properties. [Extracted from the article]

The article delves into the use of bacterial self-healing methods to repair cracks in concrete exposed to aggressive sulfate attack environments. Different types and concentrations of bacteria were studied for their impact on the mechanical properties and crack healing capabilities of concrete, with optimal results seen at a 2.5% bacterial content. Analysis confirmed the presence of calcium carbonate and calcite crystals in bacterial concrete, indicating effective fracture repair. Overall, the study suggests that bacterial concrete shows improved crack healing rates and mechanical properties compared to traditional concrete, with potential applications in sustainable construction practices. [Extracted from the article]

Throughout history, architectural heritage has been constructed using masonry, clay or stone elements, and lime‐based mortars. Over time, old buildings are subjected to different degrees of movement and degradation, leading to the formation of microcracks. Water dissolves and transports lime in mortar, but when the water evaporates, the lime is deposited and heals cracks in a process known as autogenous healing. Lime‐based mortars can regain some mechanical properties due to their healing capacity, given certain conditions. In the present work, a constitutive formulation has been developed to simulate cracking and healing in lime‐based mortars. The proposed model captures the residual displacements within cracks, associated with interacting crack surface asperities, as well as the healing effect on mechanical properties. A new approach is described which expresses these mechanisms mathematically within a micromechanical formulation. The proposed model was validated by comparing the outputs with experimental data. The results show that the new continuum micromechanical damage‐healing model could capture the damage‐healing cycle with good accuracy. [ABSTRACT FROM AUTHOR]

Microcapsule technology is a promising approach for enhancing the self-healing ability of asphalt pavements. In this study, the self-healing behavior of melamine-urea-formaldehyde (MUF) microcapsules was investigated. The microcapsules were synthesized using an in situ polymerization method. The proposed healing indicators, combined with fluorescence tracing technology, were used to evaluate the release behavior and sustained repair effect of the microcapsules at different damage levels, healing intervals, aging degrees, and healing temperatures. The results showed that most microcapsules survived at low damage levels, whereas larger microcapsules were more likely to rupture and release the rejuvenators. The sustained self-healing effect of the microcapsules could effectively repair internal damage within the asphalt pavement over an extended service life. Aged asphalt was particularly susceptible to the activation of microcapsules, leading to increased self-healing and the provision of additional rejuvenators for damaged asphalt mastic. Additionally, the self-healing of asphalt mastic with microcapsules had a critical temperature threshold. Microcapsules could enhance the fatigue and self-healing performance of asphalt mastic only when the healing temperature was below a certain value; otherwise, they may lead to adverse effects. The critical healing temperature threshold for thin-film oven testing (TFOT)-aged asphalt increased from approximately 30°C to about 45°C after PAV aging. This study provides a better understanding of the self-healing behavior of microcapsule asphalt, as well as the factors affecting the release behavior and sustained repair effects of the microcapsules. These results can be used to optimize the design and implementation of microcapsule technology to enhance the durability and sustainability of asphalt pavements. [ABSTRACT FROM AUTHOR]

Pavement researchers have sought to develop more environmentally friendly asphalt that effectively mitigates the consumption of natural resources and maintenance costs. They have noted that using durable asphalt with improved self-healing can achieve these goals. Technologies like warm-mix asphalt or calcium capsules can help the economy and substantially reduce environmental impact. These aims can be attained with technologies such as warm-mix asphalt (WMA) and calcium alginate capsules. This study evaluates the effect of Sasobit, which is utilized as a typical modifier for WMA, long-term aging (LTA) and calcium alginate capsules on the self-healing performance and mechanical properties of asphalt mixture by using different tests such as resilient modulus, indirect tensile strength (ITS), fracture test on semicircular bending (SCB) specimens and edge notched disk bend (ENDB) specimens. According to Findings, long–term aging and Sasobit negatively affect the self-healing performance of mixtures, although capsules improve it. Also, ENDB specimens have lower healing values than SCB specimens; however, due to longer crack length, ENDB specimens have more capsules incorporated in healing performance compared to SCB specimens. As a result, this paper notes that the properties of asphalt binder not only have a great effect on the self-healing performance of the mix but also have a significant impact on the action of capsules on healing cracks. [ABSTRACT FROM AUTHOR]

Dynamic cross-linked networks (DCNs) endow thermoset rubber with self-healability and recyclability to extend its lifetime and alleviate environmental pollution. However, the contradiction between high self-healing and mechanical properties in DCNs rubber is always difficult to be resolved. Herein, we used boronic ester (BO) and Diels-Alder dynamic covalent bonds (DA) to synthesize polybutadiene-based dual networks rubber (PB-BO-DA) via thiol-ene reaction. This approach achieved a tensile strength of 16.46 MPa and 99% self-healing efficiency, facilitated by extensive intermolecular interactions (π-π packing and N-B coordination) and fully dynamic cross-linking. In addition, multiple dynamic cross-linked networks (MDCNs) polybutadiene-based rubber also show excellent shape memory ability and recyclability. This strategy might open a helpful pathway to fabricate intelligent multifunctional polymers with high strength and high self-healing efficiency. [ABSTRACT FROM AUTHOR]

It is difficult to obtain sustainable and fast self-healing polyurethane materials with excellent mechanical properties at low-temperature. In this work, we prepared a series of bio-based polyurethane materials were synthesized with HMDI, Polytetramethylene ether glycol and a vanillin-based chain extender containing dynamic imine bonds. By adjusting the ratio of soft and hard segments, As the content of hard segments increased, the storage modulus and tensile strength of the material increased, the elongation at break decreased, and the heat resistance improved. The results showed that this advanced polyurethane displayed excellent mechanical and self-healing properties due to the presence of a large number of hard segment structures with dynamic imine bonds. Moreover, the tight arrangement of hydrogen bonds can promote the exchange of dynamic imine bonds and endow the material with body-temperature self-healing ability. It can recover to 98% of its original stress in 20 min at 36°C. [ABSTRACT FROM AUTHOR]

Despite extensive efforts devoted to developing self‐healing materials in the past half‐century, very limited successes are reported for ceramics or metals. Reported self‐healing materials usually have low healing strength (megapascal) and long healing time (hours), and the healing of ceramics or metals normally requires external stimuli. Here, we report on intrinsic, highly efficient self‐healing phenomena in Ti3AlC2 MAX phase nanowires at room temperature, which exhibit both ceramic and metallic properties. In situ transmission electron microscopy tensile testing reveals that the fracture strength of 2.1 GPa is achieved on the fractured Ti3AlC2 nanowire after self‐healing for 5 min, corresponding to the self‐healing efficiency of 36.2%, and the smaller the diameter, the higher the self‐healing efficiency. The underlying mechanisms are uncovered by atomic‐resolution characterizations combined with atomic simulations. The highly efficient self‐healing of Ti3AlC2 is attributed to the cleavage behavior, atomic migrations, and rebonding on fracture surfaces. Al atoms trapped between partially filled Al layers on both fracture surfaces act as obstacles for the TiAl rebonding and are responsible for the size effect. These findings provide new insights into developing high‐performance micro‐ or nano‐devices, especially those that require high security and long service lifetime. [ABSTRACT FROM AUTHOR]

To address the environmentally friendly issue of fire prevention and extinguishing materials in coal mines, a new biomass gel material was prepared using sodium carboxymethyl cellulose (CMC) as the matrix, ferro aluminum citrate (Fe-AlCit) as the cross-linking agent, and gluconic acid-δ-lactone (GDL) as the pH modifier. Through performance tests of gel micromorphology, thermal stability, viscoelasticity and yield stress, it was found that the CMC-3 gel material with a ratio of 2.5% CMC + 4% Fe-AlCit +2% GDL had a dense surface structure, good thermal stability and moderate viscosity, which was the most suitable for pipeline transport. A metal coordination bond favorable to the stability of CMC-3 gel is formed by the carboxylate ion in CMC and the double high-valent metal ions Fe3+ and Al3+ dissociated by Fe-AlCit. CMC-3 gel exhibits excellent fire prevention and extinguishing properties. The results of the programmed warming experiments showed that the inhibition rate of the coal sample treated with CMC-3 gel against CO and C2H4 gases reached 44.84% and 46.57% at 220°C, respectively, and the growth rate of the activation energy in the first and second stage reached 17.63% and 22.68%, respectively, which plays a significant inhibitory role. The infrared spectroscopy test showed that after adding CMC-3 gel, the content of -OH and Ar-C-O in the coal samples was reduced by 49.58% and 40.82%, respectively, and the content of stable C=C in the aromatics was increased by 6.14%, which effectively blocked the coal-oxygen chain reaction and reduced the tendency of coal spontaneous combustion. The thermogravimetric test showed that the characteristic temperature points of the coal sample treated with CMC-3 gel were all increased to different degrees. The fire extinguishing test showed that CMC-3 gel could significantly reduce the temperature of coal sample and extinguish the coal fire quickly. Moreover, the CMC-3 gel material also has excellent self-healing properties, which can self-repair the damaged network through the abundant reversible hydrogen and ionic bonds inside the gel in only 90 s. The study has certain guiding significance for the development of efficient and environmentally friendly self-healing mining fire prevention and extinguishing materials. [ABSTRACT FROM AUTHOR]

The directional and dynamic hydrogen bonds are of vital importance for both nucleic acids and proteins, but they naturally apply strong multiple hydrogen bonds in pendant groups and weak single hydrogen bond in the backbone. The hierarchy and orthogonality of multiple and single hydrogen bonds in biological systems inspire to elegantly tailor the supramolecular polymeric materials for robust mechanical properties. Herein, this work has fabricated dynamic ultrastrong and tough supramolecular materials through bioinspired rational design of strong multiple hydrogen bonds in pendant groups and weak single hydrogen bond in the backbone. Based on quadruple hydrogen bonds of ureidopyrimidinone and single hydrogen bond of amide, the supramolecular polymer with optimized hierarchical hydrogen bonds possesses high tensile strength and strong toughness of 30.6 MPa and 74.0 MJ m−3, respectively. Meanwhile, the dynamic dissociation and reformation of the hierarchical hydrogen bonds endow the supramolecular polymer with efficient crack resistance, self‐healing, recyclability, and high energy dissipation. Flexible and self‐healing conductors can be prepared by blending the supramolecular polymer with liquid metal in a simple manner. Therefore, this work expects that the plenty of hydrogen bonding pairs in the supramolecular toolkit provide many opportunities to produce robust and tough supramolecular polymeric materials without covalent crosslinking. [ABSTRACT FROM AUTHOR]

The corrosion of calcium-magnesium-aluminosilicate (CMAS) is a critical degradation mechanism for the hot sections of aircraft engines, particularly affecting abradable components where inherent defects complicate the prevention of rapid CMAS melt penetration. To address this challenge, Ti 3 AlC 2 was incorporated into the porous LaMgAl 11 O 19 abradables at concentrations of 5–20 wt% as both a self-healing agent and sintering aid. Annealing at 1200 °C markedly improved crack closure and pore isolation within the coating, with these effects intensifying with higher Ti 3 AlC 2 concentrations, and resulted in the retention of excess TiO 2. CMAS interaction tests conducted at 1300 °C demonstrated that only the abradables with 20 wt% Ti 3 AlC 2 addition significantly reduced the penetration of CMAS melt. This effect is attributed to the densification of the abradables caused by self-healing, which blocks the propagation of CMAS along defect channels, and the role of TiO 2 as a nucleating agent that facilitates the crystallization of CMAS and the precipitation of CaAl 2 Si 2 O 8. The La/Ca ratio in the solid solutions related to LaMgAl 11 O 19 and LaTi 2 Al 9 O 19 can be used to reflect the corrosion level of platelet-like grains, where a value below 1 is likely to trigger their dissolution. [ABSTRACT FROM AUTHOR]

With the waste of resources caused by human activities, it has gradually become an increasingly prominent social problem. The development of self-healing polymers in the field of insulation has attracted widespread attention. Develop polymer matrices with efficient healing efficiency and sound insulation properties to achieve green and sustainable resource conservation. In addition, improving the dielectric properties of intrinsic self-healing matrices has been a hot topic. In this work, we developed a new PEI matrix-modified self-healing polymer substrate that provides a breakdown field strength of 240 kV/mm and self-healing properties at room temperature, this has significantly improved the dielectric properties over other previously reported self-healing polymers. In addition to the abovementioned performance, we found significant differences in thermodynamic behavior in the synthesized end-modified polymers. By dielectric characterization (LCR), the breakdown composite can be left at room temperature for 60 min, and the material can recover 80 % of the initial properties without external intervention(This is demonstrated by the fact that its DC conductivity at 60 min of autonomous healing was significantly changed from that of the freshly electrically pierced DC conductivity and remained around 5.38 × 10−11 S/cm for a longer period of time thereafter). The microscopic morphology of the modified PEI matrix was observed by scanning electron microscopy (SEM) and EDS surface elemental analysis, which further supports the existence of metal coordination structures. These findings can further deepen the thinking of self-healing dielectric composites. The work inspired by this may break the limits and take self-healing composite dielectric materials to a new height. [ABSTRACT FROM AUTHOR]

The traditional packaging concept has reached its limits when it comes to ensuring the quality of food and extending its shelf life. Compared to traditional packaging materials, food packaging with self-healing function is becoming more and more popular. This is because they can automatically repair the damaged area, restore the original properties and prevent the decline of food quality and loss of nutrients. Materials based on various self-healing mechanisms have been developed and used on a laboratory scale in the form of coatings and films for food packaging. However, more efforts are needed for the commercial application of these new self-healing packaging materials. Understanding the self-healing mechanism of these packaging materials is very important for their commercial application. This article first discusses the self-healing mechanism of different packaging materials and compares the self-healing efficiency of self-healing materials under different conditions. Then, the application potential of self-healing coatings and films in the food industry is systematically analyzed. Finally, we give an outlook on the application of self-healing materials in the field of food packaging. [ABSTRACT FROM AUTHOR]

Intrinsic self-healing waterborne polyurethane (WPU) is an environmentally friendly, economically viable, and practical novel intelligent material. However, the key to achieving practical applications lies in the remote activation of repair in self-healing materials and the excellent mechanical properties of the matrix. In this study, we introduce quadruple hydrogen bonding in the polyurethane backbone. We have incorporated a novel two-dimensional sheet-like material, MXene, to achieve visible light remote-driven self-healing of material hydrogen bonds while enhancing the material's mechanical properties. By utilizing the MXene supernatant, this approach not only resolves the issues of poor stability and easy sedimentation of MXene nanosheets in water-based polymers but also helps to prevent resource wastage. Our research results demonstrate that the composite film exhibits a tensile strength of 6.55 MPa and a fracture elongation of 604%. Additionally, quadruple hydrogen bonds in the WPU chains enable rapid self-healing of microcracks under visible light irradiation at 300 mW/cm2, with complete disappearance within 80 min. [ABSTRACT FROM AUTHOR]

The use of microcapsules as preservative vessels for healing materials has led to a great revolution in the repair of materials. Microcapsules have been used in medicine, agriculture, metallurgy and mechanics. In civil engineering applications, microcapsules are usually used for the self-healing of concrete, asphalt and cementitious materials. Concrete and cement are widely used in civil engineering and are the predominant construction materials worldwide. The objective of this study was to design and produce urea–formaldehyde microcapsules for the recovery of reactive powder concrete (RPC). It was found that RPC specimens with and without microcapsules exhibited different behaviours. All of the RPC specimens containing microcapsules were found to have lower strengths than specimens without microcapsules. The smallest reductions in compressive strength were observed in specimens with a microcapsule content of 4–6% by weight of cement. The healing ratio of compressive strength increased with an increase in the weight percentage of microcapsules. Scanning electron microscopy and energy-dispersive spectroscopy were used to observe the process of crack healing, and the results showed that the cracks were filled with healing products. [ABSTRACT FROM AUTHOR]

This work examines the effect of temperature on the self-healing of asphalt mixture, and various laboratory tests were performed to find out qualitative and quantitative properties of asphalt material. Asphalt fatigue life and bending strength were determined using a three-point bending test and a four-point beam fatigue test. Test specimens were heated at various temperatures ranging from 20°C to 40°C for various periods, including the 20, 40, 60, 80, and 100 s. The strength recovery ratios at temperatures 20°C, 25°C, 30°C, 35°C, 40°C were 7%, 30%, 36%, 40%, 45%, respectively. The maximum healing index values for bitumen with penetration grades of 60/70 and 80/100 were 0.4 and 0.5 at temperatures between 37°C and 40°C. A 60 s period was chosen as the ideal period for achieving the highest recovery ratio for both bitumen specimens. It was observed that critical factor affecting the asphalt's capacity for self-healing is temperature, and the maximum healing index was found at temperatures between 37°C and 40°C. [ABSTRACT FROM AUTHOR]

Hot-mix asphalts are composite materials with self-healing properties: cracks in pavements constructed with these asphalts can close without external help. However, this self-healing process is slow, and cracks may reopen quickly. To increase the self-healing ratio and accelerate the healing process, capsules containing two different types of waste oil (vegetable and mineral oil) were added to the mixture at four different proportions (0.25%, 0.50%, 0.75%, and 1.00% by weight of the mixture). This research evaluated the effect of the capsule addition on the strength of the mixture against cracking. Experiments using samples with added semicircular capsules and samples containing no added capsules were carried out according to the linear elastic and elastic–plastic fracture mechanical principles. The self-healing properties of the hot-mix asphalt were determined. The results showed that the highest strength against cracking at low temperature was found in the sample with a proportion of 0.25% capsules of both types (waste vegetable and mineral oil). In addition, the oil released from the capsules increased the self-healing properties of the hot-mix asphalt. Samples fractured at 0°C had better healing than the samples fractured at 25°C. [ABSTRACT FROM AUTHOR]

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This paper presents the deployment of Runge-Kutta method to overcome the main challenge in analysis of failure of aircraft wing structure subjected to wind pressure and point loading. Failure phenomenon of any structure is time dependents and is typically referred as dynamic in engineering mechanics and is fairly a complex to investigate. In this context, the dynamic analysis concept has successfully implemented by using computer program in SCILAB software. The numerical technique is adopted as Runge-Kutta fourth order (RK4) method for performing dynamic behaviour of wind structure. The demonstration of failure mode of wing structure is based on function of time. The numerical approach is deemed to provide a detailed description of these phenomena affecting the overall dynamic of failure envelope of wing structure. The parametric study is presented; likewise the effect on failure of wing structure by changing different wind pressure, length and moment, respectively. The wing structure is analytically validated against available literature. Finally, others important failure results obtained from this analysis has discussed in detail. [ABSTRACT FROM AUTHOR]

The self-healing of metallic material is a relatively new area in materials engineering. It is inspired by the biological process of healing. This work analyzes the self-healing behaviour of metals-matrix composite. The semi-solid metal processing technology was opted to prepare an aluminium-based self-healing metal-matrix composite. Nitinol is the alloy produced by combining nickel and titanium in a 1:1 ratio, with the wires of the same incorporated within the aluminium matrix during the process. Analysis of the recovery rate of the self-healing material and microstructural investigation of the metal matrix composite is the objective of this research work. The deployment of shape memory wire provides the ability to recover the matrix material even from plastic strain. Nitinol exhibits a shape memory effect by the transformation of the phase. Integration of A356 alloy with nitinol wire enables the material to regain its original shape and dimension by heat as an external stimulus. Semi-solid metal process via rapid slurry formation technique handled delicately so that self-healing effect should not diminish. Microstructural evaluation indicates fair integration of the reinforcement within the matrix material. Analysis of crack closure shows 44.277% positive recovery of the deformed surface. [ABSTRACT FROM AUTHOR]

Self-assembled non-covalent nanoparticle-polymer hybrids, that can combine a variety of desired properties in a single material with highly dynamic structure, have great potential in the field of functional nanosystems. In this study, we present a method for preparing such hybrids from silica nanoparticles and polymer structures of polystyrene-block-polyacrylic acid (PS-b-PAA). We show that the surface chemistry of the nanoparticles has a major influence on the encapsulation efficiency and the localization of the particles in the vesicles. Furthermore, an increase in vesicle size was observed with higher vesicle loading. A particular highlight of this work is that the morphology of the hybrids could be subsequently modified by adjusting the solvent composition. It was also found that the presence of the particles led to faster transitions due to the increased free energy of the system. This type of morphological change therefore offers promising potential applications, such as self-healing materials. [ABSTRACT FROM AUTHOR]

The capacity of biological tissues to undergo self‐healing is crucial for the performance of functions and the continuation of life. Conventional intrinsic self‐healing materials demonstrate analogous functionality depending on the dissociation‐recombination of reversible bonds with no need of extra repair agents. However, the trade‐off relationship between mechanical strength and self‐healing kinetics in intrinsic self‐healing systems, coupled with the lack of additional functionality, restricts their service life and practical applications. Diversified highly ordered structures in organisms significantly affect the energy dissipation mechanism, signal transmission efficiency, and molecular network reconstruction capability due to their multi‐dimensional differentiated macroscopic composite constructions, microscopic orientation textures, and topologies/bonding types at molecular level. These architectures exhibit distinctive strengthening mechanisms and functionalities, which provide valuable references. This review aims at providing the current status of advanced intrinsic self‐healing materials with biomimetic highly ordered internal micro/nanostructures. Through highlighting specific examples, the classifications, design inspirations, and fabrication strategies of these newly developed materials based on integrating dynamic interactions with ordered nano/microstructures are outlined. Furthermore, the strengthening and self‐healing balance mechanisms, structure–functionalization relationships, and potential application values are discussed. The review concludes with a perspective on the challenges, opportunities, and prospects for the development, application, and promotion of self‐healable materials with bio‐like ordered architectures. [ABSTRACT FROM AUTHOR]

Cracks in concrete, including recycled aggregate concrete (RAC), lead to durability issues from substance penetration. This study introduces microbial precipitation for crack healing in RAC. It substitutes 50% and 100% of natural coarse aggregate with recycled coarse aggregate and replaces cement with blends of hydrated lime and brick powder. Self-healing effectiveness is assessed through compressive strength, RCPT, UPV, and microscopic analysis. Results show complete healing of 0.58 mm cracks over 56 days, with compressive strength regain ranging from 94% to 56%. RCPT variation ratios range from 142% to 173%. Microstructural analysis through FESEM, EDS, and XRD reveals microbial precipitate properties. FTIR and TGA analyses explore CaCO3 through infrared absorbance and mass variation with temperature. The study suggests that microbial-induced self-healing improves strength and durability in recycled aggregate concrete. [ABSTRACT FROM AUTHOR]

This work reports a kind of thermal and stress dual-induced nano-SiC-modified microcapsule that is applied to asphalt pavement to improve its self-healing performance. For this purpose, the microcapsules needed to contain a regenerator and be stable in an asphalt mixture. In addition, the microcapsules needed to have good wave-absorbing and temperature-raising properties to realize the dual-mechanism-induced release of microcapsules. In the first step in this study, heat-stressed double microcapsules were prepared. Then, the properties of the microcapsules—including basic properties, stability, mechanical properties, and wave-absorbing and temperature-raising properties—were tested. Finally, the self-healing mechanism of the microcapsules was observed. The results show that the nano-SiC-modified microcapsules have a high core content (87.6%), suitable particle size (average particle size of 53.50 µm), high thermal stability (mass loss of 2.92% at 150~170 °C), high construction stability (survival rate of more than 80%), high storage stability (loss rate of 2.35% at 49 d), and high mechanical properties (Young's modulus and nano-hardness of 3.15 Gpa and 0.54 Gpa, respectively). Compared with microcapsules without nano-SiC, the thermal conductivity of the 10% nano-SiC-modified microcapsules increased by 21.6%, their specific heat capacity decreased by 10.45%, and their thermal diffusion coefficient increased by 36.96% after microwave heating for 6 min. [ABSTRACT FROM AUTHOR]

Oxide ceramic electrolytes (OCEs) have great potential for solid-state lithium metal (Li0) battery applications because, in theory, their high elastic modulus provides better resistance to Li0 dendrite growth. However, in practice, OCEs can hardly survive critical current densities higher than 1 mA/cm2. Key issues that contribute to the breakdown of OCEs include Li0 penetration promoted by grain boundaries (GBs), uncontrolled side reactions at electrode-OCE interfaces, and, equally importantly, defects evolution (e.g., void growth and crack propagation) that leads to local current concentration and mechanical failure inside and on OCEs. Here, taking advantage of a dynamically crosslinked aprotic polymer with non-covalent –CH3⋯CF3 bonds, we developed a plastic ceramic electrolyte (PCE) by hybridizing the polymer framework with ionically conductive ceramics. Using in-situ synchrotron X-ray technique and Cryogenic transmission electron microscopy (Cryo-TEM), we uncover that the PCE exhibits self-healing/repairing capability through a two-step dynamic defects removal mechanism. This significantly suppresses the generation of hotspots for Li0 penetration and chemomechanical degradations, resulting in durability beyond 2000 hours in Li0-Li0 cells at 1 mA/cm2. Furthermore, by introducing a polyacrylate buffer layer between PCE and Li0-anode, long cycle life >3600 cycles was achieved when paired with a 4.2 V zero-strain cathode, all under near-zero stack pressure. Self-healing is an appealing property for solid-state battery electrolytes to combat Li metal dendrites that pierce through the solid electrolyte. Here, authors report a self-healing electrolyte and observe its self-repairing kinetics in real-time using advanced microscopy. [ABSTRACT FROM AUTHOR]

In the process of curing or service, epoxy resin is prone to crack damage due to complex stress, resulting in material performance degradation and other catastrophic accidents. Self‐healing microcapsules offer an effective strategy to address the aforementioned issues and enhance the long‐term durability of materials. However, traditional microcapsules face challenges in achieving non‐contact repair, as the healing agent requires high temperature or other extreme conditions to achieve curing, which necessitates the artificial provision of these conditions. Moreover, such extreme conditions may accelerate equipment aging or negatively impact the matrix material. To address these issues, this paper reports a photosensitive microcapsule that can achieve healing by natural light for non‐contact self‐healing of insulating composites. In particular, SiO2 nanoparticles are incorporated into the shell of the microcapsules to construct a UV shielding layer, effectively preventing premature curing and failure of the untriggered microcapsules. Experimental results indicate that the proposed photosensitive microcapsule@SiO2 exhibits excellent thermal stability, remaining intact at temperatures up to 200°C. With a healing agent content of approximately 77.5%, the photosensitive microcapsule@SiO2 ensures effective repair. Furthermore, when cross‐linked with epoxy resin, it has minimal negative impact on the epoxy matrix, with a slight improvement in mechanical properties. The composites demonstrate outstanding self‐healing performance in response to mechanical scratch damage. Without the need for any artificial stimuli, the healing process can be easily activated by natural light, facilitating intelligent, contactless, and autonomous self‐healing. [ABSTRACT FROM AUTHOR]

Nowadays, self-healing materials have been studied actively in electronics, soft robotics, aerospace, and automobiles because they can prolong the life span of the materials. However, overcoming the trade-off relationship between mechanical properties and self-healing performance is challenging. Herein, graphene oxide-polyaniline (GO-PANI) filler was introduced to overcome this challenge because GO has a highly excellent modulus, and nitrogen atoms in PANI can endow a self-healing ability through hydrogen bonds. Aside from the hydrogen bond in PANI, the hydrogen bond in the carbonyl group and the disulfide exchange bond in the epoxy matrix also helped the materials heal efficiently. Therefore, the modulus of SV-GPN1 (Self-healing Vitrimer-GO-PANI1) reached 770 MPa, and a 65.0% healing efficiency was demonstrated. The modulus and self-healing efficiency were enhanced after adding GO-PANI filler. The self-healing ability, however, deteriorated when adding more GO-PANI filler because it hindered the collision between the molecules. Meanwhile, SV-GPN1 was excellent in reproducibility, which was proven by the experiment that 16.50 mm thick SV-GPN1 also displayed a self-healing ability. Thus, SV-GPN1 can be applied to structural materials in industries like aerospace because of its self-healing ability, excellent modulus, and reproducibility. [ABSTRACT FROM AUTHOR]

In this study, the practical application of self-healing asphalt mixtures incorporating steel wool fibers and induction heating was investigated, expanding upon previous research that primarily assessed the self-healing properties rather than optimizing the heating process. Specifically, the aim was to enhance the induction heating methodology for a semi-dense asphalt concrete mixture (AC 16 Surf 35/50 S). In this research, the induction heating parameters were refined to improve the self-healing capabilities, focusing on the following three key aspects: (i) energy consumption, (ii) heating rate, and (iii) heating homogeneity. The findings reveal that the current intensity, the percentage of ferromagnetic additives, and coil shape are critical for achieving optimal heating conditions. Higher current intensity and additive percentage correlate with improved heating speed and reduced energy consumption. Additionally, variations in coil shape significantly influence the heating uniformity. Although asphalt mixtures with steel slag coarse aggregates exhibit slightly higher specific heat, this aggregate type is preferable for sustainability, as it allows for the recycling of industrial waste. The optimized mixtures can rapidly reach high temperatures, facilitating effective crack repair. This innovation offers a durable, environmentally friendly, and cost-effective solution for road maintenance, thereby enhancing the longevity and performance of asphalt pavements. [ABSTRACT FROM AUTHOR]

Dynamic non-covalent interactions between polycarbonate soft segments have been proposed for explaining the intrinsic self-healing of polyurethanes synthesized with polycarbonate polyols (PUs) at 20 °C. However, these self-healing PUs showed insufficient mechanical properties, and their adhesion properties have not been explored yet. Different PUs with self-healing at 20 °C, acceptable mechanical properties, and high shear strengths (similar to the highest ones reported in the literature) were synthesized by using blends of polycarbonate polyols of molecular weights 1000 and 2000 Da (CD1000 + CD2000). Their structural, thermal, rheological, mechanical, and adhesion (single lap-shear tests) properties were assessed. PUs with higher CD1000 polyol contents exhibited shorter self-healing times and dominant viscous properties due to the higher amount of free carbonate groups, significant carbonate–carbonate interactions, and low micro-phase separation. As the CD2000 polyol content in the PUs increased, slower kinetics and longer self-healing times and higher mechanical and adhesion properties were obtained due to a dominant rheological elastic behavior, soft segments with higher crystallinities, and greater micro-phase separation. All PUs synthesized with CD1000 + CD2000 blends exhibited a mixed phase due to interactions between polycarbonate soft segments of different lengths which favored the self-healing and mobility of the polymer chains, resulting in increased mechanical properties. [ABSTRACT FROM AUTHOR]

This study examines the use of rice husk ash (RHA) and incinerated sugarcane press mud (ISPM) as precursors in the lime/pozzolan geopolymer system and the effect of the bacterium Lysinibacillus sp. WH on the mechanical properties and microstructures. The RHA-to-ISPM ratio was varied, and the geopolymer pastes were cured at ambient temperature. The results show that an increase of ISPM content up to 5% improves strength and reduces water absorption and voids, while higher ISPM levels beyond 5% degrade the quality of geopolymer paste. An increase in ISPM content reduces setting times due to an increase amount of calcium in the pastes. Notably, the addition of bacteria resulting in a reduction of setting times has been proved for the first time in this work. Moreover, the addition of bacteria can enhance all mechanical properties and introduce self-healing abilities, with microcracks healing within < 20 days of treatment, regardless of mix proportions. Microstructural studies, using a scanning electron microscope (SEM), Fourier Transform Infrared Microscopy (FT-IR), X-ray diffraction (XRD), and Rietveld refinement analysis, reveal that bacteria increase cristobalite, and decrease quartz, thus resulting in strength enhancement of geopolymer pastes. Furthermore, this work is the first to provide evidence that bacteria tend to reduce the efflorescence formation as confirmed by a decrease in gaylussite. These findings pave ways to the production of more sustainable geopolymer systems via upcycling wastes and prolonging service life due to bacterial activity. [ABSTRACT FROM AUTHOR]

[Display omitted] Stone-built cultural heritage faces threats from natural forces and anthropogenic pollutants, including local climate, acid rain, and outdoor conditions like temperature fluctuations and wind exposure, all of which impact their structural integrity and lead to their degradation. The development of a water-based, environmentally-friendly protective coatings that meet a combination of requirements posed by the diversity of the substrates, different environmental conditions, and structures with complex geometries remains a formidable challenge, given the numerous obstacles faced by current conservation strategies. Here we report the structural, electrical, and mechanical characterization, along with performance testing, of a nanostructured hydrophilic and self-healing hybrid coating based on hydroxyapatite (HAp) nanocrystals and polyelectrolyte multilayers (PEM), formed in-situ on Greek marble through a simple spray layer-by-layer surface functionalization technique. The polyelectrolyte-hydroxyapatite multilayer (PHM) structure resembled the design of naturally forming trabecular bone, attained at a short procedural time. It exhibited chemical affinity, aesthetical compatibility and resistance to weathering while offering reversibility. The proposed method is able to generate micron-sized coatings with controlled properties, such as adhesion and self-healing, leading to less weathered surfaces. Our results show that the PHM is a highly effective protective material that can be applied for stone protection and other similar applications. [ABSTRACT FROM AUTHOR]

The incorporation of self‐healing properties to repair scratches (or other minor damage) has revolutionized the coating industry by increasing service life, sustainability, and optical appearance. This work addresses challenges with the robustness of self‐healing coatings through the inclusion of surface‐tethered covalently adaptable networks (CANs). Surface‐initiated polymerization is combined with spray‐coating to deposit polymers to produce coatings with reversible crosslinks to the tethered chains. These robust coatings are based on reversible vinylogous urethane bonds using 2‐(acetoacetoxy)ethyl methacrylate‐based polymers and tris(2‐aminoethyl) amine (TREN). Here, TREN enables reversible covalent bonding between the spray‐coated and surface‐tethered polymers. Without this polymer brush layer, the physisorbed CAN coatings fail to self‐heal completely, are labile to solvent, and exhibit shear delamination upon scratching. The utility of this tethered coating approach is highlighted through its ability to autonomously self‐heal incisions within seconds at elevated temperatures, or more steadily under ambient conditions. The key to these advancements is the use of polymer brushes as a primer layer to attach the CAN to enhance healing and improve the environmental robustness of the coating. [ABSTRACT FROM AUTHOR]

Cement-based materials are essential components of engineered barrier systems in geological disposal facilities for both hazardous and radioactive waste. This review provides a comprehensive examination of the application of cement-based materials in various aspects of geological disposal. Specifically, it details the use of cement paste backfill for mine tailings, which has shown a reduction in permeability by 95 %, and cementitious grouts for ground stabilization, achieving a compressive strength increase of 20 %. Shotcrete applications for rock support demonstrate enhanced adhesion properties, with a 30 % improvement in bond strength. Cementitious matrices for low- and intermediate-level waste immobilization have been optimized to reduce leachability by 40 %. Concrete containers for high-level waste and spent fuel are discussed, highlighting their ability to maintain structural integrity under high radiation and thermal loads for over 100 years. Cement-based seals for repository closure are also examined, with a focus on their self-sealing properties and long-term durability. The long-term performance of these engineered barriers is influenced by deterioration processes such as physical, chemical, and biological degradation. This review discusses optimization strategies, including the development of alternative binder systems that reduce CO₂ emissions by 30 %, the incorporation of nanoengineered cements that enhance mechanical properties by 25 %, the use of smart additives that provide real-time monitoring capabilities, and the creation of multifunctional composites that combine strength and self-healing properties. Future research directions are highlighted, emphasizing the need for advanced predictive models, innovative material formulations, and integrated monitoring technologies to ensure the long-term safety and performance of geological disposal systems. [ABSTRACT FROM AUTHOR]

The polymeric materials can simultaneously possess high mechanical properties and outstanding self‐healing performance under mild condition have found widespread applications in various fields. However, this type of polymers is exceedingly rare due to the trade‐off between mechanical robustness and chain flexibility for healing. In this study, we designed a facile strategy for synergistic integration of dynamic acylsemicarbazide (ASC) bonds and disulfide bonds into polyurethane elastomer by the reaction between 3,3′‐dithiobis(propionohydrazide) and isocyanate‐terminated Pre‐PU. The obtained elastomer ASC‐SS‐PU not only possesses an outstanding tensile strength (17.1 MPa), good stretchability (735%) and high toughness (57.16 MJ·m−3), but also exhibits excellent self‐healing performance under mild condition. The healing efficiency of the damaged ASC‐SS‐PU samples (breakage rate >90%) can reach over 70% healing at 60°C for 40 min, which is much lower than conventional ASC‐based PU elastomer. Considering the simple and easy‐to‐scaleup preparation process and commercially available low‐cost raw materials, outstanding mechanical strength and toughness, as well as high healing efficiency under mild condition, the ASC‐SS‐PU elastomer as self‐healing but strong materials have great potential for use in various fields. [ABSTRACT FROM AUTHOR]

Human skin is essential for perception, encompassing haptic, thermal, proprioceptive, and pain-sensing functions through ion movement. Additionally, it is mechanically resilient and self-healing for protection. Inspired by these unique properties, researchers have attempted to develop stretchable, self-healing sensors based on ion dynamics. However, most self-healing sensors reported to date suffer from low fracture strength and toughness. In this work, we present an ion-based self-healing electronic skin with exceptionally high fracture strength and toughness. We enhanced self-healing polymers and ionic conductors by introducing two types of orthogonal dynamic crosslinking bonds: dynamic aromatic disulfide bonds and 2-ureido-4-pyrimidone moieties. These dynamic bonds provide autonomous self-healing and high mechanical toughness even in the presence of ionic liquids. As a result, our self-healing polymer and self-healing ionic conductor exhibit remarkable stretchability (700%, 850%), fracture strength (34 MPa, 30 MPa), and toughness (78.5 MJ/m3, 87.3 MJ/m3), the highest values reported among self-healing ionic conductors to date. Using our materials, we developed various fully self-healing sensors and a soft gripper capable of autonomously recovering from mechanical damage. By integrating these components, we created a comprehensive self-healing electronic skin suitable for soft robotics applications. Stretchable and self-healing sensors based on ion dynamics usually suffer from low fracture strength and toughness. Here, the authors describe an ion-based self-healing electronic skin with autonomous self-healing, high mechanical toughness and fracture strength. [ABSTRACT FROM AUTHOR]

Nano-zirconium oxide particles were immobilized into chitosan via electrospraying technique to obtain organic-inorganic hybrid microcapsules (CZ) serving as self-healing anticorrosion materials for the enhancement of epoxy coating. Assessment of produced materials through adequate characterizations revealed hybrid microcapsules possessed spherical morphology with a mean size of 300 μm and thermal stability at 700oC up to ~ 50%. Subsequently, CZ was incorporated into an epoxy coating matrix to develop a self-healing coating, CZPx, for carbon steel protection. SEM and EIS analysis of scratched CZPx coating at 14 days of immersion in a corrosive medium confirmed the self-healing and anticorrosion capabilities of the coating with the impedance at the coating-substrate interface increasing from 2.01 × 106 to 1.22 × 107 (ohm cm2) between the 7th to 14th day of immersion. The barrier property of CZPx was determined through capacitance (CPEdl) to be higher than neat epoxy coating with a stronger impedance to the ingression of corrosion agents after the 14th day of immersion. Due to the unique feature of prepared CZ that allows their absorption of corrosion ions and formation of cross-linkages, self-healing was triggered upon the introduction of defects. The inhibitive nature of CZ provided superior anticorrosion properties to epoxy coating. [ABSTRACT FROM AUTHOR]