Breaking Elongation Research Articles

Novel indicator film incorporating Dendrobium orchid extract and TiO2 nanoparticles for seafood freshness monitoring

This study aimed to develop a pH indicator film using a combination of hydrocolloids (polyvinyl alcohol, carboxymethyl cellulose, and rice flour; PCR film), Dendrobium orchid flower (DOF) extract, and TiO2 nanoparticles to monitor shrimp and crab freshness during 9 days of cold storage. LC-MS/MS analysis identified a rare anthocyanin, cyanidin-3-[6-sinapoyl-2-O-(2-(sinapoyl)glucosyl)-glucoside], in the DOF extract, responsible for its color expression. The DOF extract showed a clear color variation in different solutions (pH 1–13). TiO2 nanoparticles influenced the film's thickness, tensile strength (TS), elongation at break (EB), water vapor permeability (WVP), and color properties. Structural changes due to nanoparticles were confirmed via Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. PCR+DOF+8%TiO2 film showed the highest TS (13.75 ± 0.60 MPa), EB (2.24 ± 1.42 %), and WVP (3.57 ± 1.12 × 10-11 g·m·Pa-1·m-2·s-1) values and was more sensitive to ammonia vapor than acetic acid vapor. In practical applications, the film could effectively indicate shrimp spoilage through color change but was less precise for crab samples. The film effectively indicated shrimp spoilage through a color shift to green on the 4th day, correlating with total viable count and volatile nitrogen levels exceeding safe consumption thresholds. Thus, this film could serve as an efficient diagnostic tool for monitoring seafood spoilage.

Calcium alginate reinforced zwitterionic double network hydrogel with mechanical robustness and antimicrobial activity for freshwater shrimp spoilage detection

Hydrogel indicators promise to monitor food spoilage, but their poor mechanics can cause defects in transport. Herein, a novel zwitterionic double network (DN) hydrogel was developed by polymerizing arylamide and sulfobetaine methacrylate in an alginate-Ca2+ system. This hydrogel exhibited enhanced mechanical properties, including a maximum 2087 % breaking elongation and 135 ± 12 kJ/m3 toughness, significantly outperforming the current zwitterionic DN hydrogels, which typically exhibit less than 1800 % breaking elongation, capable of supporting 150 g—136 times its own weight. Importantly, it also demonstrated excellent anti-fatigue and tear resistance, with a tearing energy of 2200 ± 180 J/m2. The abundant zwitterionic polymers, hydroxyl groups, and amino groups within hydrogel contribute to its strong adhesiveness to various substrates. Additionally, the hydrogel exhibited antimicrobial activity against E. coli and S. aureus. Furthermore, a pH/NH3 dual-sensitive hydrogel indicator, using phenol red, bromocresol purple, and their mixtures in ratios of 1:1, 1:2, and 2:1, was developed for monitoring shrimp freshness. The results showed that the hydrogel indicator with phenol red, effective at 4°C and 25°C, showed clear color changes (ΔE > 80) in response to spoilage and strong correlations between ΔE and TVB-N (R2 > 0.98) and pH (R2 > 0.97), surpassing the existing hydrogel indicators used for shrimp freshness monitoring, which generally have a correlation coefficient of only 0.86. This novel dual-responsive hydrogel, with excellent mechanical performance and TVB-N sensitivity, is suitable for real-time freshness monitoring in intelligent packaging.

Pea protein-p-coumaric acid conjugate-based antioxidant film: The relationship between protein structure and film properties after covalent bonding

In this study, pea protein isolates (PPI) have been used to make conjugates by covalent binding with p-coumaric acid (p-CA), and the effect of conjugation on PPI structural characteristics and the structural, optical, mechanical, and physicochemical properties of conjugate-based films were investigated. The conjugation with p-CA unfolds the tertiary structure of PPI and significantly reduces the surface charge. A tendency of aggregation with increasing p-CA addition was proposed. The conjugate-based films show stronger tensile strength (TS) and better water barrier properties than PPI-based films. However, no significant improvement of the elongation at break (EAB) and thermal stability was found for conjugate-based films. FTIR spectroscopic and zeta-potential analyses indicated that such improved film properties could be attributed to the enhancement of hydrogen bonds and weakening of electrostatic repulsion between conjugate-conjugate. Additionally, the conjugates impart the antioxidant activity to the films as confirmed by DPPH scavenging capacity. This study demonstrates the potential of using pea protein-phenolic acid conjugate to make PPI-based films with improved mechanical properties, water barrier properties, and antioxidant activity.

Biodegradable rice bran insoluble dietary fiber-chitosan blend films: Characterization and potential applications

A composite film of insoluble dietary fiber (IDF) from rice bran (RB) blended with chitosan (IDF-CS film) was prepared and characterized. The thermal stability, thickness, tensile strength, colour, water vapour permeability (WVP) and oil permeability (PO) of the film were analysed. SEM micrographs revealed the porous morphology of the film. XRD spectra suggested an amorphous crystalline nature of the film. FTIR spectra showed a 1600 cm−1 peak in chitosan and dietary fiber, indicating C=O stretching, and TGA showed good thermal stability under various temperatures. The thickness increased to 0.104 mm in the film containing IDF -Chitosan2:2. The tensile strength (TS) was enhanced to 18.420 MPa in the film containing IDF -Chitosan2:2. The elongation at break (EB) was higher (12.65%) in films containing low concentrations of IDF-Chitosan0.5:0.5. WVP was enhanced to 5.856 ×10-12 g·cm/cm2·Pa·s in the film containing IDF 2:2. The prepared film showed excellent soil-degrading properties, with a degradation rate of 96% after 15 days. The IDF-CS film demonstrated a substantial inhibitory potential against Gram-positive bacteria. The scavenging capacities of the degradable film were 96.5% for DPPH and 98.8% for ABTS. Moreover, the viability of cervical HeLa cell line was 10% at 200 μg/ml compared with that of the positive control (4%). Significant cytomorphological changes leading to necrosis in treated cells were observed using light and fluorescence microscopy. The film (IDF-CS) developed is environmentally friendly and could be used as a novel therapeutic material for treating bacterial pathogens, scavenging free radicals, and inhibiting cancer cell proliferation.

Novel antimicrobial packaging film with finger wrinkles structures based on egg white and chitosan coating for fruit preservation.

Developing a high-barrier, green, and sustainable functional packaging film material to address food safety is urgently needed but remains a significant challenge. Natural biopolymers possess the potential to serve as contemporary eco-friendly food packaging materials due to their exceptional biocompatibility and biodegradability. Herein, we present a novel class of renewable and degradable films fashioned from Egg white protein (EWP) and chitosan (CS) biopolymers. And we detected their structural, physical, and functional properties to ensure a nanocomposite film with the optimal performances. Scanning electron microscopy (SEM) images demonstrated a consistent enhancement in the crinkle level of the composite film as the mass ratio of CS increased. Furthermore, the tensile strength (TS) and elongation at break (EAB) of these films were enhanced to 402.6 % and 107.9 %, respectively. Nevertheless, the oxygen permeability (OP) and water vapor permeability (WVP) were notably reduced to 68.1 % and 93.3 %, respectively. Compared to EWP/CS/Cur0, the antibacterial rate of prepared EWP/CS/Cur(Xie et al., 2024 [3]) films were enhanced to 105.4 % and 183.9 % for E. coli and S. aureus, respectively. During banana and green grape preservation, these functional films significantly retarded the decline in weight and firmness. Therefore, EWP/CS films augmented with bioactive materials could potentially serve as preservation packaging, exhibiting notable ecological advantages and recyclability potential, thus demonstrating considerable potential as a substitution for conventional plastic storage packages.

Hybrid electrospinning of pullulan and citrus pectin to load astaxanthin: Preparation, characterization, and functional evaluation

Pullulan (PUL) is a widely used agent for electrospinning. However, nanofibers electrospun solely from PUL exhibit a highly hydrophilic nature and a bead-like structure. In this study, 1–5 wt% citrus pectin (CP) was introduced to construct a hybrid electrospinning system to investigate the effects of CP concentration on the properties of the electrospun nanofibers. The results reveal that the bead-like structure, rigidity, and hydrophobicity of the nanofibers underwent significant improvements following the introduction of CP. Furthermore, to demonstrate the protective effect of the nanofiber on astaxanthin, 0.1 wt% astaxanthin was encapsulated in the hybrid electrospinning system containing 5 wt% CP. The results show that after encapsulating astaxanthin, the rigidity of the nanofiber further increased, with a tensile strength of 12.5 MPa and a break elongation of 2.9 %. Additionally, the nanofiber system demonstrates excellent protection of the antioxidant activity of astaxanthin under UV exposure compared to free astaxanthin.

Effect of austempering temperatures on mechanical properties of dual matrix structure austempered ductile iron

Abstract This study investigates the effect of the austempering temperatures on the microstructures and mechanical properties of austempered ductile iron with dual-matrix structure (DMS-ADI). An unalloyed ferritic ductile iron bar samples were intercritically austenitized at 810 °C for 60 min and austempered at different austempering temperatures (300 °C, 325 °C, 350 °C, and 375 °C) for 120 min. Microstructural and mechanical characterization were examined using optical microscopes, scanning electron microscopes (SEM), X-ray diffraction (XRD) analyses, hardness, and tensile tests. Experimental results showed that the DMS-ADI samples exhibit a dual-phase structure consisting of proeutectoid ferrite + ausferrite structures. The volume fraction of ausferrite (42.5–47.5 %) was almost stable in all austempering temperatures in DMS-ADI samples. The high-carbon retained austenite volume fraction, and its carbon content increased with increased austempering temperatures. At austempering temperatures up to 350 °C, strength and hardness increased, while energy at break and total elongation decreased. The strength and hardness decreased, while energy at break and total elongation increased at 375 °C austempering temperature. All DMS-ADI samples exhibited ductile fracture surfaces except for those austempered at 350 °C. The highest (σ UTS = 590 MPa and ε T = 18.8 %) and lowest (σ UTS = 434 MPa and ε T = 28.5 %) mechanical properties were obtained in DMS-ADI samples austempered at 350 °C and 300 °C, respectively.

Disclosing the UV aging mechanisms of polyamide 66 industrial fiber on the base of the multi-scale structural evolutions

This study investigated the changes in the properties of polyamide 66 (PA66) industrial fibers during UV aging and explored the underlying UV aging mechanisms through structural data analysis across varying length scales. The findings reveal a three-stage progression in the deterioration of mechanical properties due to UV aging. Initially, in the pre-aging stage (t ≤ 1 day), both mechanical properties and microscopic structural parameters remain stable, showing no significant changes. Following this, UV-induced degradation and concurrent recrystallization in the amorphous region result in a decline in mechanical parameters as the aging process continues, albeit with varying magnitudes across the stages. A notable decrease in tenacity and elongation at break is observed in the mid-aging stage (1 day < t ≤ 49 days). While the formation of low-melting-point microcrystals enhances crystallinity and crystalline size, the predominant effect of molecular chain scission due to UV exposure leads to a significant increase in carbonyl group content and a marked decrease in intrinsic viscosity. Furthermore, the formation of microcrystals hinders oxygen diffusion, resulting in the gradual stabilization of intrinsic viscosity and carbonyl content in the late-aging stage (t > 49 days), which significantly slows the deterioration of mechanical properties. These results indicate that UV-induced molecular degradation is the primary driver of changes in break elongation, while the development of new crystalline structures within the fibers contributes to the preservation of mechanical properties.

“Mending with silk” enhances aged silk with mechanical and antibacterial properties

The reinforcement and preservation of historical silk are crucial for its continued research, heritage, and display. Herein, silk fibroin (SF) and carboxymethyl chitosan (CMCS) were utilized as raw materials to reinforce aged silk via two reinforcement methods, with transglutaminase (TGase) serving as a catalytic cross-linking agent. The covalent and non-covalent bond network formed by TGase catalytic cross-linking significantly improved the mechanical properties of aging silk, and CMCS as an antibacterial material gave excellent antibacterial properties of the aged silk. Compared with aged silk, the breaking stress and elongation at break of the aged silk after reinforcement are increased by 257.9% and 293.7% respectively. The antibacterial rate of the reinforced aged silk against Escherichia coli (E. coli) and Streptococcus aureus (S. aureus) exceeded 90%. Under accelerated simulated aging conditions, the aging rate of the reinforced silk was significantly reduced, demonstrating notable aging resistance. Notably, the one-step enhanced aged silk outperformed the two-step enhanced aged silk in all performance evaluations, while the appearance of the aged silk was not affected. This work provides a green and efficient process for the reinforcement and protection of silk-based cultural relics and the application of silk cultural relics protection materials.

Flexible self-adhesive high-performance electromagnetic shielding film

Electromagnetic shielding materials are those that can mitigate electromagnetic interference (EMI) by absorbing, reflecting, or scattering electromagnetic waves. With the advancement of research, electromagnetic shielding materials are not only expected to have high EMI shielding effectiveness but also to integrate other functional properties. In this study, a flexible self-adhesive electromagnetic shielding film with high shielding effectiveness (SET), named rGO@DTPP, has been developed. Leveraging multiple loss mechanisms, the SET of rGO@DTPP can peak at up to 55 dB. Additionally, it possesses excellent self-adhesive properties, enabling it to adhere to a variety of material surfaces. Notably, it exhibits a high adhesive strength of 0.21 N/cm on the skin surface. The composite film also has breaking elongation of up to 40 %, and it features a highly conductive thin film when in contact with the skin, thus adhering well to the skin's surface. This makes it an outstanding material for flexible, wearable applications.

Unidirectional moisture-wicking PAN/BTO-PVDF/ZnO all fibrous bilayer breathable electronic skin for health sensing

All fibrous electronic skin based on excellent flexibility and piezoelectric properties could be widely applied in monitoring and healthcare sensing. The accumulative moisture during application scenarios, just as violent sweat or a damp environment, can affect the stability and sensitivity of the piezoelectric signal. Here, a bilayer piezoelectric sensor was fabricated using a layer-by-layer electrospinning technique. The inner layer is composed of hydrophobic piezoelectric polyvinylidene fluoride (PVDF)-zinc oxide (ZnO) nanofibers, while the outer layer consists of hydrophilic piezoelectric polyacrylonitrile (PAN)-barium titanate (BTO) nanofibers. The unidirectional moisture-wicking performance based on the hydrophilic-hydrophobic gradient of PVDF/ZnO-PAN/BTO nanofiber membranes (PZ-PBNF) could conduct liquid within 1 s. Incorporating inorganic ZnO and BTO nanoparticles provides a practical approach to enhancing the piezoelectric output performance (277.5 mV). These fibrous PZ-PBNF membranes also exhibit excellent stretchability properties (breaking elongation of 110 %) and air permeability (12.065 mm/s). This innovative electronic skin with directional water transport and sensing functions could ensure long-term wear comfort for practical application in emerging wearable technologies and all healthcare ranges.

High‐strength silicone polyurea/DOCIT coating with anti‐biofouling and self‐healing characteristics

AbstractA new organosilicon‐based polyurea/DOCIT composite coating with excellent mechanical, self‐healing characteristics has been successfully prepared in this paper. The optimal ratio of the two isocyanates has been explored to acquire the highest mechanical strength with 8.56 MPa and best tensile properties with 763%. The breaking strength and elongation remain 3.50 MPa and 915% with 1% antimicrobial agent DOCIT. The self‐healing characteristic comes from dense hydrogen and dynamic disulfide bonds between molecule chains. The composite coating exhibited ideal bacterial resistances for 98.02% and 96.75% against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively. The adhesion of chlorella was significantly reduced by approximately 86.48%. This work provides a promising avenue for the development of high‐performance silicone polyurea coatings for marine anti‐biofouling.

Compensation control and design methods for excavations in deep soft rocks

During the excavation and support process in deep soft rocks, complex conditions such as high stress and strong disturbance can be encountered. The complex conditions can cause failure of the support system. Aiming at stability control in deep soft rocks, we proposed the excavation compensation theory. A new high strength and high toughness material was developed. The breaking load and elongation of the new material are 1.59 and 1.78 times that of common bolt materials. To overcome the problem that the CABLE element in FLAC3D cannot simulate failure of support structures, the numerical model for the whole process of force-breaking-anchorage failure simulation (FBAS) for bolts (cables) was established. The numerical experiments on the excavation compensation control of deep soft rock were carried out. The excavation compensation control mechanism of high strength and high toughness material was clarified. Compared with the common support scheme, the highly prestressed support has a maximum increase of 90.24% in radial stress compensation rate and a maximum increase of 67.85% in deformation control rate. The results illustrate the rationality of the excavation compensation theory. The compensation design method of excavations in deep soft rocks was proposed and applied in a deep soft rock chamber. The monitoring indicated that the maximum surrounding rock deformation is 180 mm, reduced by 64% compared to the common support. The deformation of the chamber was controlled and the surrounding rock was stable.

Enhanced physical properties and water resistance of films using modified starch blend with poly(vinyl alcohol)

Research into sustainable biopolymer films is increasingly focused on finding viable alternatives to petroleum-based plastics. This study aims to address these challenges by examining the performance of a series of films prepared using polyvinyl alcohol (PVA) with varying degrees of saponification (DS) and polymerization (DP), combined with two modified starch: hydroxypropyl starch (HPS) and sodium octenylsuccinate starch (OctS). The findings demonstrate that increased PVA saponification and polymerization levels greatly improved the physical properties of the PVA/Starch blends because of the interactions and intermolecular entanglement between the PVA and starch chains. By altering the PVA and starch formulations, the blend films' tensile qualities and water resistance were greatly improved; at a 7:3 ratio, the highest tensile strength (TS) is ∼17.4 MPa, and elongation at break (EAB) is ∼476.8 %. The tensile properties and water resistance of the blend films were significantly enhanced by varying the PVA and starch formulations, achieving the highest tensile strength (17.4 MPa) and elongation at break (476.8 %) at a 7:3 ratio. Moreover, the PVA/OctS-7 blend exhibited superior water durability, and high transparency, with the lowest swelling (∼108.6 %) and certain wet strength, as well as varied solubility behaviors in different pH solutions, rendering it appropriate for use in packaging applications. As a result, PVA/Starch blend films' functional qualities can be significantly improved, making them appear as viable substitutes for petrochemical plastic packaging.

Optimization of novel sustainable Dictyota mertensii alginate films with beeswax using a simplex centroid mixture design

The environmental risks of synthetic polymers drive the need for innovative and sustainable film and packaging solutions. This study optimized the formulation of films composed of alginate derived from the brown seaweed Dictyota mertensii (ADM), glycerol, beeswax, and tween 80, aiming to improve their properties. A simplex-centroid blend design was employed to develop and optimize the composite films. The films were characterized based on their morphological properties, moisture content (MC), contact angle (CA), solubility (S), water vapor permeability (WVP), color parameters (L∗, a∗, and b∗), opacity, tensile strength (TS), elongation at break (EB), and elastic modulus (E). Contour surfaces were plotted from the studied variables, fourth-order polynomial models were predicted, the influence of the blend components was analyzed, and the response variables were subjected to analysis of variance (ANOVA) and the F test with 95% confidence. The predicted conditions were experimentally validated. MC, WVP, solubility, opacity, a∗, and b∗ were minimized, whereas CA, L∗, TS, EB, and E were maximized, resulting in MC = 6.85%, WVP = 16.37 g mm/h.kPa.m2, S = 28.87%, CA = 83.86°, Opacity = 5.60 AU.nm.mm−1, L∗ = 70.31, a∗ = 4.79, b∗ = 21.00, TS = 11.76 MPa, EB = 12.70%, and E = 96.47 MPa. The overall desirability index was 0.70, resulting in an optimal biopolymer matrix of 75.00% ADM, 5.00% glycerol, 7.50% beeswax, and 12.50% Tween 80. The results highlight the potential of alginate films made from the brown seaweed Dictyota mertensii and the sustainable use of natural marine resources.

Innovative preparation of polyimide/polysulfone amide (PI/PSA) membrane-pore-like nanofibers with biomimetic penguin feather shaft structure and thermal insulation performances

The white-browed penguin can survive in extreme environments due to its unique feather structure. The feather shafts of penguins are porous, separated by the membrane-pore-like structure made of keratin fiber membranes. The feather branches are densely arranged around the feather shafts. This unique structure provides inspiration for researchers. In this work, we developed a simple method to construct polyimide/polysulfone amide (PI/PSA) membrane-pore-like structure nanofibers resembling penguin feather shafts and studied the effects of different low-boiling point solvents (tetrahydrofuran (THF), ethyl acetate (EA), and acetone (AC)) on the morphology, tensile properties, and thermal insulation properties of PI/PSA membrane-pore-like structure nanofibers. Comprehensive characterization was also performed using scanning electron microscope, total reflection infrared spectrometer, X-ray diffractometer, universal testing machine, thermal conductivity meter, pore size analyzer, thermal gravimetric analyzer, infrared thermal imaging instruments, and thermocouple testing instruments. The results showed that when the mass ratio of THF to N, N-dimethylacetamide (DMAC) was 20/80, the prepared PI/PSA membrane-pore-like structure nanofibers exhibited excellent thermal insulation properties, with a low thermal conductivity of 0.0436 W·m−1·K−1, a breaking strength of 7.72 ± 2.64 MPa, and a breaking elongation of 8.19 ± 4.07 %. The biomimetic membrane-pore-like structure with excellent thermal insulation properties is expected to be applied in various fields, such as heat-protective clothing and architectural coatings in harsh environments.

Physico-mechanical Properties of Nano Bio-films For Application in Food Packaging

Petroleum-based packaging has long dominated the packaging industry, raising environmental concerns. As a result, the packaging industry has started using nano bio-plastics. Incorporating nanoparticles, nano bio-plastic packaging helps in prolonging product shelf life. Additionally, packaging manufactured of nano bio-plastic is made of biodegradable polymers. Nano bio-films made from polylactic acid (PLA) and nanoclay were produced using a solvent casting process. 1.0%, 3.0% and 5.0% (wt.) of nanoclay were added to the PLA solution. The mechanical, chemical, morphological and transparency properties of nano bio-films were investigated. To improve their suitability for food packaging applications, tensile test, Fourier-transform Infrared Spectroscopy (FTIR), scanning electron microscopy (SEM) and UV-barrier test were performed. With tensile strength (TS) of 30.36 MPa and elongation at break (EAB) of 7.05%, respectively, nano bio-films with 3.0 wt. % nanoclay demonstrated higher mechanical properties than pure PLA film with about 35% of increment. In aspects of FTIR analysis, no significant differences were found with both nano bio-films and pure PLA film. The SEM morphology shows that adding nanoclay at 3.0 wt. % improves the adhesion between the PLA matrix and the nanoclay. The addition of nanoclay had a minimal impact on the PLA film's transparency, and it was interesting to see that nanoclay concentration of 1.0 wt. % and 3.0 wt. % had roughly the same light transmission values of 84.86% and 83.95%, respectively. According to the findings of this study, the PLA nano bio-film with 3.0 wt% nanoclay exhibits the optimum physico-mechanical properties.

Flexible and Flame Retardant Cotton Fiber-reinforced CS/CNF/EP Composites For a Sensitive Fire Warning

Enhancing fire safety performance in resin-based composites is critical for mitigating fire hazards. Composites that provide early warnings during initial fire stages and maintain prolonged alarm capabilities under flame exposure are essential for minimizing injuries and property damage. This study employs chitosan (CS) as a cross-linking and char-forming agent, while carbon nanofiber (CNF) acts as a flame retardant and conductive component. Cotton fiber-reinforced chitosan/carbon nanofiber composites with varying epoxy and CNF contents (CS/CNF/EP) were prepared through a straightforward low-temperature curing process (40 °C, 4 h). Crosslinking polymerization between chitosan and epoxy was confirmed via Fourier Transform Infrared Spectroscopy (FTIR). The presence of the tough structure of CS and the rigid structure of EP results in a synergistic toughening and reinforcement effect in the CS/CNF/EP composites. Additionally, due to the carbon facilitating properties of CS and the enhanced conductivity of CNF, the composites exhibit a sensitive fire alarm functionality. At 35 % epoxy content, the CS/CNF/EP composites demonstrated exceptional properties, including mechanical flexibility (tensile strength of 7.09 MPa and breaking elongation of 129.05 %) and outstanding flame retardancy (LOI of 32.3 % and UL-94 V-0 rating). These composites provided a rapid alarm (∼1 s), sustaining a 263 s warning under flame exposure and over 35 min post-flame removal. These findings indicate that CS/CNF/EP composites, integrating mechanical flexibility, flame retardancy, and superior fire warning properties, present significant potential applications in fire safety engineering.

Kill Two Birds with One Stone: Cracking Lithography Technology for High-Performance Flexible Metallic Network Transparent Conductors and Metallic Micronano Sheets.

Flexible electronics have sparked a wide range of exciting applications, such as flexible display technologies, lighting, sensing, etc. Flexible conductors are essential components of flexible electronics and seriously affect efficiency and overall performance. Here, a facile and kill-two-birds-with-one-stone strategy of cracking lithography technology has been proposed to simultaneously fabricate two high-performance flexible conductors, flexible metallic network transparent conductors (f-NTCs) and metallic micronano sheets (MMNSs). The PET substrate flexible transparent conductors (FTCs) based on this strategy yield 88.1% transparency within the visible spectrum and a sheet resistance of 9 Ω/sq. In addition, the FTCs show exceptional mechanical stability, with the sheet resistance remaining virtually unchanged even after 6000 s of bending tests. Subsequently, the remaining MMNSs are recycled to manufacture a Ag paste, showing a very low conductive percolation threshold (∼13%) and excellent flexibility with 140% breaking elongation. After 1000 s of stretching tests, it showed excellent mechanical stability. Furthermore, flexible electroluminescent devices based on the FTCs and sensors fabricated with MMNSs both show excellent performance, demonstrating their potential wide applications in flexible electronics.

Polymerizable deep eutectic solvent-gels synthesized in situ under molecular engineering control exhibit excellent adhesion, freeze resistance, as well as stretching and humidity sensing capabilities

Hydrogels generally do not adhere well to different substrates and freeze at sub-zero temperatures, limiting their application. In this study, the strategy of replacing water in hydrogels with deep eutectic solvents (DES) was used to address these challenges. Specifically, choline chloride (ChCl) as hydrogen bond acceptor, acrylic acid (AA) and itaconic acid (IA) as hydrogen bond donors and polymerizable monomers constitute PDES. Afterwards, PDES-gel (PG) was obtained by adding a thermal initiator to polymerize AA and IA in PDES. PG has the following characteristics, because PG is almost water-free, it has remarkable low-temperature tolerance without any phase change at −60 °C to 20 °C. Thanks to the carboxyl groups and chloride ions contained in PG, it can form non-covalent interactions such as hydrogen bonding and ionic interactions with different substrates, so PG can adhere to various substrate surfaces. Furthermore, the breaking elongation of the novelty PG was up to ca. 960 %, tensile strength ca. 1 MPa, outstanding transparency with an average light transmittance of about 95 % in the visible-light range. Ultimately, the novel PG exhibited certain capabilities for moisture detection and deformation sensing. The new PDES-gel material developed using PDES is expected to provide new ideas for the advancement of wearable devices.