Dual Cross-Linked Networks Reinforced Polyimide Foams with Outstanding Piezoelectric Properties and Heat Resistance Performance.

The application of traditional isocyanate-based polyimide (PI) foams is highly hindered due to limited flame retardancy, poor mechanical properties, and relatively single functionality. Herein, we propose an effective method to fabricate dual cross-linked polyimide/bismaleimide (PI-BMI) foams with outstanding heat resistance and enhanced mechanical properties by incorporating bis(3-ethyl-5-methyl-4-maleimidophenyl)methane (ME-BMI) as the interpenetrating network. The results show that the prepared PI-BMI composite foams exhibit enhanced mechanical properties with lightweight characteristics (23-80 kg·m-3). When the ME-BMI loading reached 120 wt %, the tensile and compressive strength of PI-BMI composite foam can reach 1.9 and 7.8 MPa, which are 9.6 and 63.3 times higher than that of pure PI foam, respectively. In comparison with PIF-0, the 10% heat loss temperature (Td,10%) of PIF-90 improved by 156 °C. Moreover, the PI-BMI foam piezoelectric sensor containing fluorine groups presents a short response time (14.22 ms), high sensitivity (0.266 V/N), and outstanding stability (10 000 cycles). Besides, the sensor can accurately monitor human activity in different states. This work provides a promising strategy for designing multifunctional PI foams, making them suitable for applications in aerospace and microelectronics.

Development and characterization of tilapia skin collagen-inulin oleogel as the potential fat substitute in beef patty formulations.

The effects of inulin addition, olive oil content, and ultrasonic treatment on the rheological, texture, and structural properties of collagen-based oleogels were investigated in this study. Furthermore, the fat substitution ability of the oleogel in low-fat beef patties was evaluated. Initially, a uniform and dense network cross-linked structure was found when the ratio of collagen to inulin complex was 1:5. The oleogel sample exhibited good stability and oil binding ability with an additional amount of 50 % olive oil. Ultrasonic treatment improved the stability of the oleogel structure in all samples. Additionally, the addition of inulin reduced cooking loss in beef patties. Beef patties prepared at a 50 % fat substitution level showed physical properties that were the least different from those of pure adipose tissue (control group), which could significantly reduce the content of saturated fatty acids and improve the storage stability of beef patties. This study provided guidance for the application of collagen-inulin oleogel in food processing.

Modulation of Mechanical Properties of Silica-Filled Silicone Rubber by Cross-Linked Network Structure.

Associating molecular structure and mechanical properties is important for silicone rubber design. Although silicone rubbers are widely used due to their odourless, non-toxic, and high- and low-temperature resistance advantages, their application and development are still limited by their poor mechanical properties. The mechanical properties of silicone rubbers can be regulated by designing the cross-link density and cross-linking structure, and altering the molar contents of vinyl in the side groups of methyl vinyl silicone rubber (MVQ) leads to different cross-linking structures and cross-linking densities in the vulcanized rubber. Therefore, this study investigated the differences in molecular parameters and molecular chain structures of unprocessed MVQ rubbers with different vinyl contents. The results showed that MVQ rubbers with high vinyl contents were branched polymers, better facilitating the cross-linking reaction than MVQ rubbers with low vinyl contents. In addition, silicone rubbers with different vinyl contents were co-cross-linked to introduce an inhomogeneous cross-linked network in the silicone rubber to improve its mechanical properties. The cross-linked network properties were analysed by the Flory-Rehner model and Mooney-Rivlin plots, and it was found that the long chains in the sparsely cross-linked domains of the network favoured high elongation at break and the short chains in the densely cross-linked domains contributed to high modulus, which could satisfy the functions of reinforcing and toughening the rubber materials at the same time. It was also found by analysing the filler network and aggregate morphology that the inhomogeneous cross-linked network led to an improvement in the dispersion of silica in the rubber and a significant improvement in the mechanical properties of silicone rubber.

Preparation and Properties of Fluorinated Poly(aryl ether)s with Ultralow Water Absorption and Dielectric Constant by Cross-Linked Network Strategy.

Poly(aryl ether) materials are used in a wide range of applications in the communications and microelectronics fields for their outstanding mechanical and dielectric properties. In order to further improve the comprehensive performance, this work reports a series of cross-linkable poly(aryl ether)s (UCL-PAEn) containing trifluoroisopropyl and perfluorobiphenyl structures using 2,2-bis(4-hydroxyphenyl)hexafluoropropane, 2,2'-diallyl bisphenol A, and perfluorobiphenyl as starting materials. Their chemical structures and the effect of changes in the allyl content on the properties are thoroughly investigated. Owing to the introduction of fluorine atoms and cross-linked networks, the cross-linked poly(aryl ether) films present low dielectric constants (Dk = 1.93-2.24 at 1 MHz), low water absorption (0.14% -0.25%), and hydrophobic film surfaces (94.3-99.4°). Additionally, because of the presence of cross-linked networks, the CL-PAEn films exhibit superior thermal stability, with the 5% weight loss temperatures all above 445 °C and the maximum thermal decomposition rate temperatures all above 550 °C. The cross-linked films also demonstrate excellent mechanical properties, with tensile strength in the range of 57.1 -146.7 MPa and tensile modulus in the range of 1.8 GPa-4.5 GPa.

Polyvinyl alcohol /chitosan biomimetic hydrogel enhanced by MXene for excellent electromagnetic shielding and pressure sensing.

Traditional electromagnetic shielding materials are difficult to realize practical applications due to excessive fillers, poor mechanical properties, and difficulty in preservation, etc. Hydrogel is a biomaterial with good biocompatibility and sustainability, which not only can overcome the aforementioned issues, but its biomimetic hierarchical porous structure also enables multifunctional applications. In this paper, a honeycomb-like unidirectional porous wall structured hydrogel is prepared by a simple freeze-thaw cycle and salting out method. Polyvinyl alcohol (PVA) and chitosan (CS) form a double cross-linked network (DN) enhanced by MXene, resulting in excellent mechanical and flexibility. Due to the synergistic effects of MXene, water, Fe3O4, abundant interfaces and micrometer porous wall structure, the electromagnetic shielding performance is enhanced. EMI SE increases by 30.7 dB as the MXene concentration increases from 0 to 1.5 wt%, and EMI SE increases from 7.9 to 66.7 dB as the water content increases from 0 to 76 %. Besides this, we encapsulate the hydrogel into a simple sensor, the signal response is rapid, the response /recovery time is 50/100 ms respectively, and it exhibits good sensitivity (0.0187 kPa-1). Different signals are generated based on variations in pressure, which holds significant importance for the development of wearable flexible sensors and information encoding.

Frequency-Dependent Dielectric Permittivity and Water Permeability in Ordered Mesoporous Silica-Grafted Fluorinated Polyimides.

Polymers with a low dielectric constant (Dk) are promising materials for high-speed communication networks, which demand exceptional thermal stability, ultralow Dk and dissipation factor, and minimum moisture absorption. In this paper, we prepared a series of novel low-Dk polyimide films containing an MCM-41-type amino-functionalized mesoporous silica (AMS) via in situ polymerization and subsequent thermal imidization and investigated their morphologies, thermal properties, frequency-dependent dielectric behaviors, and water permeabilities. Incorporating 6 wt.% AMS reduced the Dk at 1 MHz from 2.91 of the pristine fluorinated polyimide (FPI) to 2.67 of the AMS-grafted FPI (FPI-g-AMS), attributed to the free volume and low polarizability of fluorine moieties in the backbone and the incorporation of air voids within the mesoporous AMS particles. The FPI-g-AMS films presented a stable dissipation factor across a wide frequency range. Introducing a silane coupling agent increased the hydrophobicity of AMS surfaces, which inhibited the approaching of the water molecules, avoiding the hydrolysis of Si-O-Si bonds of the AMS pore walls. The increased tortuosity caused by the AMS particles also reduced water permeability. All the FPI-g-AMS films displayed excellent thermooxidative/thermomechanical stability, including a high 5% weight loss temperature (>531 °C), char residue at 800 °C (>51%), and glass transition temperature (>300 °C).

Three-dimensional cross-linked network deep eutectic gel polymer electrolyte with the self-healing ability enable by hydrogen bonds and dynamic disulfide bonds.

Solid polymer electrolytes (SPEs) are effective solutions for the development of high-performance and flexible lithium metal batteries (LMBs). However, the key problems of SPEs including low ionic conductivity and inability to repair damage have hindered their industrialization process. In this work, a three-dimensional (3D) cross-linked network gel polymer electrolyte (CNGPE) is designed. The addition of deep eutectic solvent (DES) improves the ionic conductivity of CNGPE. The hydrogen bonds and dynamic disulfide bonds in the 3D cross-linked network endow CNGPE rapid self-healing ability at ambient temperature. In addition, the addition of lithium difluoro(oxalato)borate (LiDFOB) and lithium nitrate (LiNO3) helps to form a stable solid electrolyte interface (SEI). Due to the ingenious design, the Li/CNGPE/Li symmetrical cell exhibits excellent interface stability and no short circuit occurs for more than 800 h. The assembled LiFePO4/CNGPE/Li cell exhibits a discharge specific capacity of 126 mAh g-1 after 960 cycles at 0.5C. This work has shown that the self-healing gel polymer electrolyte containing DES provides an effective and feasible method for the development of high-performance LMBs.

Rigid-flexible coupling network solid polymer electrolytes for all-solid-state lithium metal batteries.

Poor mechanical strength at working temperature and low ionic conductivity seriously hinder the application of poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) in high performance all-solid-state lithium metal batteries (LMBs). Here, we design and prepare a series of rigid-flexible coupling network SPEs (RFN-SPEs) with soft poly(ethylene glycol) (PEG) chains and rigid crosslinkers containing the benzene structure. Compared with soft crosslinkers, rigid crosslinkers provide the same amount of active crosslinking points with smaller molecular weight, and meanwhile enhance the mechanical strength of the network. Therefore, based on the rigid crosslinkers, RFN-SPEs exhibit synchronously improved ionic conductivity and mechanical strength. With these RFN-SPEs, symmetrical cells can be cycled for over 2100 h at 0.5 mA cm-2. Meanwhile, stable cycling and high-rate capability could be achieved for LMBs, revealing that SPEs with the rigid-flexible coupling network are promising electrolyte systems for all-solid-state LMBs.

Tailoring Three-Dimensional Cross-Linked Networks Based on Water-Soluble Polymeric Materials for Stable Silicon Anode.

For stable battery operation of silicon (Si)-based anodes, utilizing cross-linked three-dimensional (3D) network binders has emerged as an effective strategy to mitigate significant volume fluctuations of Si particles. In the design of cross-linked network binders, careful selection of appropriate cross-linking agents is crucial to maintaining a balance between the robustness and functionality of the network. Herein, we strategically design and optimize a 3D cross-linked network binder through a comprehensive analysis of cross-linking agents. The proposed network is composed of poly(vinyl alcohol) grafted poly(acrylic acid) (PVA-g-PAA, PVgA) and aromatic diamines. PVgA is chosen as the polymer backbone owing to its high flexibility and facile synthesis using an ecofriendly water solvent. Subsequently, an aromatic diamine is employed as a cross-linker to construct a robust amide network that features a resonance-stabilized high modulus and enhanced adhesion. Comparative investigations of three cross-linkers, 2,2'-bis(trifluoromethyl)benzidine, 3,3'-oxidianiline, and 4,4'-oxybis[3-(trifluoromethyl)aniline] (TFODA), highlight the roles of the trifluoromethyl group (-CF3) and the ether linkage. Consequently, PVgA cross-linked with TFODA (PVgA-TFODA), featuring both -CF3 and -O-, establishes a well-balanced 3D network characterized by heightened elasticity and improved binding forces. The optimized Si and SiOx/graphite composite electrodes with the PVgA-TFODA binder demonstrate impressive structural stability and stable cycling. This study offers a novel perspective on designing cross-linked network binders, showcasing the benefits of a multidimensional approach considering chemical and physical interactions.

Construction of multiple crosslinked networks for the preparation of high-performance lignin-containing cellulose nanofiber reinforced polyvinyl alcohol films.

Polyvinyl alcohol (PVA) film, a promising alternative to non-biodegradable plastic packaging films for food and medical packaging, is limited by poor water resistance. In this work, a simple solvent evaporation self-assembly was used to construct a nanophase separation structure to establish dense interfacial hydrogen bonding, covalent bonding and iron metal ion coordination interactions between lignin-containing cellulose nanofibers (LCNFs) and PVA matrix to improve the interfacial force and solve the problem of poor compatibility of LCNFs in PVA. The iron ion (Fe3+) coordination tended to combine with the more active lignin phenolic hydroxyl group to construct the nanophase separation structure. Covalent crosslinking of glutaraldehyde (GA) improved the interfacial compatibility of PVA/LCNF films, enhanced the interfacial bonding and formed a homogeneous structure. The multi-nanophase structures improved the strength and elastic modulus of the PVA/LCNF film and provided the films with extremely low water absorption, water vapor transmission rate and excellent UV-shielding. Compared with pure PVA film, PVA-10L-5Fe-3GA film had about 106.9 % higher tensile strength, 93.9 % lower water absorption and 93.4 % lower mass loss, 69.8 % lower water vapor transmission coefficient, and was able to shield UV at 200-400 nm, which is highly expected to be used in packaging films.

Permanent Shape Reconfiguration and Locally Reversible Actuation of a Carbon Nanotube/Ethylene Vinyl Acetate Copolymer Composite by Constructing a Dynamic Cross-Linked Network.

Given the rapid developments in modern devices, there is an urgent need for shape-memory polymer composites (SMPCs) in soft robots and other fields. However, it remains a challenge to endow SMPCs with both a reconfigurable permanent shape and a locally reversible shape transformation. Herein, a dynamic cross-linked network was facilely constructed in carbon nanotube/ethylene vinyl acetate copolymer (CNT/EVA) composites by designing the molecular structure of EVA. The CNT/EVA composite with 0.05 wt % CNT realized a steady-state temperature of ∼75 °C under 0.11 W/cm2 light intensity, which gave rise to remote actuation behavior. The dynamic cross-linked network along with a wide melting temperature offered opportunities for chemical and physical programming, thus realizing the achievement of the programmable three-dimensional (3D) structure and locally reversible actuation. Specifically, the CNT/EVA composite exhibited a superior permanent shape reconfiguration by activating the dynamic cross-linked network at 140 °C. The composite also showed a high reversible deformation rate of 11.1%. These features endowed the composites with the capability of transformation to 3D structure as well as locally reversible actuation performance. This work provides an attractive guideline for the future design of SMPCs with sophisticated structures and actuation capability.

Insights into the Correlation of Cross-linking Modes with Mechanical Properties for Dynamic Polymeric Networks.

Simultaneously introducing covalent and supramolecular cross-links into one system to construct dually cross-linked networks, has been proved an effective approach to prepare high-performance materials. However, so far, features and advantages of dually cross-linked networks compared with those possessing individual covalent or supramolecular cross-linking points are rarely investigated. Herein, on the basis of comparison between supramolecular polymer network (SPN), covalent polymer network (CPN) and dually cross-linked polymer network (DPN), we reveal that the dual cross-linking strategy can endow the DPN with integrated advantages of CPN and SPN. Benefiting from the energy dissipative ability along with the dissociation of host-guest complexes, the DPN shows excellent toughness and ductility similar to the SPN. Meanwhile, the elasticity of covalent cross-links in the DPN could rise the structural stability to a level comparable to the CPN, exhibiting quick deformation recovery capacity. Moreover, the DPN has the strongest breaking stress and puncture resistance among the three, proving the unique property advantages of dual cross-linking method. These findings gained from our study further deepen the understanding of dynamic polymeric networks and facilitate the preparation of high-performance elastomeric materials.

Preparation and performance of starch-based cross-linked network structured dust suppression foams for complex climatic conditions.

In complex environmental applications such as rain erosion and high-low temperatures in open-pit coal mines, the curing layer after dust suppression foam treatment is relatively poorly tolerated, resulting in poor dust suppression. This study is aimed at a high-solidification strong weather-resistant cross-linked network structure. First, oxidized starch adhesive (OSTA) was prepared by the oxidative gelatinization method to reduce the effect of the high viscosity of starch on the foaming effect. Then, OSTA, polyvinyl alcohol (PVA) and glycerol (GLY), were copolymerized with the cross-linking agent sodium trimetaphosphate (STMP), and compounded with sodium aliphatic alcohol polyoxyethylene ether sulfate (AES) and alkyl glycosides (APG-0810), a new material for dust suppression in foam (OSPG/AA) was proposed and its wetting and bonding mechanism was revealed. The results show that OSPG/AA has a viscosity of 5.5 mPa·s, a 30-day degradation of 43.564 % and a film-forming hardness of 86HA; through simulated tests in open-pit coal mine environments, it was found that the water retention of OSPG/AA is 40.0 % higher than that of water, and the dust suppression rate of PM10 is 99.04 %. The cured layer can adapt to temperature changes from -18 °C to 60 °C and remains intact after rain erosion or 24 h immersion, exhibiting good weather resistance.

Water-Soluble Polyamide Acid Binder with Fast Li+ Transfer Kinetics for Silicon Suboxide Anodes in Lithium-Ion Batteries.

Silicon suboxide (SiOx) anodes have attracted considerable attention owing to their excellent cycling performance and rate capability compared to silicon (Si) anodes. However, SiOx anodes suffer from high volume expansion similar to Si anodes, which has been a challenge in developing suitable commercial binders. In this study, a water-soluble polyamide acid (WS-PAA) binder with ionic bonds was synthesized. The amide bonds inherent in the WS-PAA binder form a stable hydrogen bond with the SiOx anode and provide sufficient mechanical strength for the prepared electrodes. In addition, the ionic bonds introduced by triethylamine (TEA) induce water solubility and new Li+ transport channels to the binder, achieving enhanced electrochemical properties for the resulting SiOx electrodes, such as cycling and rate capability. The SiOx anode with the WS-PAA binder exhibited a high initial capacity of 1004.7 mAh·g-1 at a current density of 0.8 A·g-1 and a capacity retention of 84.9% after 200 cycles. Therefore, WS-PAA is a promising binder for SiOx anodes compared with CMC and SA.

Preparation and Properties of a Novel Cross-Linked Network Waterborne Polyurethane for Wood Lacquer.

Waterborne polyurethane (WPU) is a waterborne coating with excellent physicochemical properties. Its deficiencies of water resistance, chemical resistance, staining, and hardness have limited the wide application of polyurethane in the wood lacquer market. In this study, polycarbonate diols (PCDL) were used as soft segments and WPCU was modified by cross-linking using Trimethylolpropane (TMP) to prepare polycarbonate type WPU (WPCU) with cross-linked network structure. The new wood lacquer was prepared by adding various additives and tested by applying it on wood board. The successful synthesis of WPCU was determined by FTIR testing, and the cross-linking degree of WPCU was probed by low-field NMR. The viscosity of the cross-linked WPCU emulsion showed a decreasing trend compared to the uncross-linked WPCU emulsion, and WPCU-2 had the smallest particle size. Compared with the uncrosslinked WPCU film, the crosslinked WPCU film had lower water absorption (2.2%), higher water contact angle (72.7°), excellent tensile strength (44.02 MPa), higher thermomechanical, and better water and alcohol resistance. The effect of crosslinker content on the microphase separation of WPCU chain segments on the surface roughness of the film was investigated by SEM. The wood paint prepared by WPCU emulsion has good dry heat resistance, chemical resistance, and adhesion, and the hardness of the wood paint when the TMP content is 3% reaches H. It also has good resistance to sticky stains, which can be used to develop new wood lacquer.

Polymer Gels: Classification and Recent Developments in Biomedical Applications.

Polymer gels are a valuable class of polymeric materials that have recently attracted significant interest due to the exceptional properties such as versatility, soft-structure, flexibility and stimuli-responsive, biodegradability, and biocompatibility. Based on their properties, polymer gels can be used in a wide range of applications: food industry, agriculture, biomedical, and biosensors. The utilization of polymer gels in different medical and industrial applications requires a better understanding of the formation process, the factors which affect the gel's stability, and the structure-rheological properties relationship. The present review aims to give an overview of the polymer gels, the classification of polymer gels' materials to highlight their important features, and the recent development in biomedical applications. Several perspectives on future advancement of polymer hydrogel are offered.

An Elastic Cross-Linked Binder for Silicon Anodes in Lithium-Ion Batteries with a High Mass Loading.

Due to the urgent demand for lithium-ion batteries (LIBs) with a high energy density, silicon (Si) possessing an ultrahigh capacity has aroused wide attention. However, its practical application is seriously hindered by enormous volume changes of the Si anode during cycling. Developing novel binders suitable for the Si anode has proven to be an effective strategy to improve its electrochemical performance. Herein, we constructed a three-dimensional network binder, in which the polyacrylic acid (PAA) long chains are cross-linked with one kind of amino acid, lysine (Lys). The abundant polar groups in PAA/Lys enable it to tightly adhere to the Si particles via hydrogen bonds, and the cross-linked structure prevents irreversible slipping of the PAA chains upon volume variation of the particles. The Si used was obtained from a sustainable route by recycling photovoltaic waste silicon. With high elasticity and strong adhesion, the PAA/Lys binder can effectively keep the structural integrity of the Si electrode and improve its electrochemical performance. The Si electrode using the PAA/Lys binder exhibits a good cycling stability (1008 mAh g-1 at 2 A g-1 after 250 cycles). Even with a high mass loading of 3.03 mg cm-2, the Si anode can remain stable for 100 cycles at a high fixed areal capacity of 3.03 mAh cm-2. This work gives a practical method to make stable Si electrodes using sustainable Si source and environmentally friendly amino acid-based binders.

Enhancing oxygen/moisture resistance of quantum dots by short-chain, densely cross-linked silica glass network.

Quantum dots (QDs) are facing significant photoluminescence degradation in moisture environment. In QDs-silicone composites, the poor water resistance of silicone matrix makes it easy for water and oxygen molecules to erode QDs. To tackle this issue, we proposed a new QDs protection strategy by introducing short-chain silica precursors onto the QDs' surface, so that a dense silica passivation layer could be formed onto the QDs nanoparticles. Sol-gel method based on 3-aminopropyl triethoxysilane (APTES), 3-mercaptopropyl trimethoxysilane (MPTMS), and 3-mercaptopropyl triethoxysilane (MPTES) were adopted to prepare the uniform and crack-free QDs-silica glass (QD-glass). Because of the crosslinking of short-chain precursors, the formed silica glass possesses 38.6% smaller pore width and 68.6% lower pore volume than silicone, indicating its denser cross-linked network surrounding QDs. After 360 h water immersion, the QDs-glass demonstrated a 6% enhancement in red-light peak intensity, and maintained a stable full width at half maximum (FWHM) and peak wavelength, proving its excellent water-resistant ability. However, the conventional QDs-silicone composites not only showed a decrease of 75.3% in red-light peak intensity, but also a broadened FWHM and a redshifted peak wavelength after water immersion. QDs-glass also showed superior photostability after 132 h exposure to blue light. Red-light peak intensity of QDs-glass remained 87.3% of the initial while that of QDs-silicone decreased to 19.8%. And the intensity of QDs-glass dropped to 62.3% of that under 20 °C after thermal treatment of 160 °C. Besides, under increasing driving currents, the light conversion efficiency drop of QDs-glass is only one fifth that of QDs-silicone. Based on the QDs-glass, the white light-emitting diodes was achieved with a high luminous efficiency of 126.5 lm W-1and a high color rendering index of 95.4. Thus, the newly proposed QD-glass has great significance in guaranteeing the working reliability of QDs-converted devices against moisture and high-power environment.

Comonomer-Tuned Gel Electrolyte Enables Ultralong Cycle Life of Solid-State Lithium Metal Batteries.

Rechargeable lithium metal batteries (LMBs) are considered the "holy grail" of energy storage systems. Unfortunately, uncontrollable dendritic lithium growth inherent in these batteries has prevented their practical applications. The benefits of solid-state electrolyte for LMBs are limited due to the common compromise between ionic conductivity and mechanical property. This work proposes a mechanism for simultaneous improvement in ionic conductivity and mechanical strength of gel polymer electrolyte (GPE) which is based on tunable cross-linked polymer network through adjusting monomer ratios. With increasing bisphenol A ethoxylate dimethacrylate (E2BADMA) and poly(ethylene glycol) diacrylate (PEGDA) mass ratios in GPE precursors, the formed polymer network experienced a composition evolution from a 3D cross-linked mono PEGDA network to triple PEGDA, E2BADMA, and PEGDA/E2BADMA networks and then to dual E2BADMA and PEGDA/E2BADMA networks, accompanied by the increase in both storage modulus (from 6 to 37 MPa) and ionic conductivity (from 0.06 to 0.44 mS cm-1). As a result, the E2BADMA/PEGDA mass ratio of 2:1 facilitates the successful fabrication of a dual-network-supported GPE (PEEPL-12) with a mechanical strength of 37 MPa and superior electrochemical properties (a high ionic conductivity of 0.44 mS cm-1 and a wide electrochemical stability window of 4.85 V vs Li/Li+). Such polymer electrolyte-based symmetric lithium metal batteries delivered a long cycle life (2000 h at 0.1 mA cm-2 and 0.1 mAh cm-2), and the Li|PEEPL-12|LiFePO4 cell delivered a high capacity of 140 mAh g-1 at the 100th cycle at the current density of 0.1 C (1 C = 170 mAh g-1). A more thorough investigation indicated the formation of a stable solid electrolyte interphase layer on a lithium metal anode. These extraordinary features open up a venue for fabrication of advanced polymer electrolyte for long-cycle-life lithium metal batteries.

Dual Cross-Linked Starch-Borax Double Network Hydrogels with Tough and Self-Healing Properties.

Herein, we have fabricated starch-borax double cross-linked network (DC) hydrogels with tough and self-healing properties using a one-pot method. The addition of borax significantly increased the storage modulus and loss modulus of these starch-borax DC hydrogels. The maximum compression stress (~288 kPa) of starch-borax DC hydrogels containing 5% borax was about ten times greater than that of a pure-starch hydrogel. The texture profile analysis values of the DC hydrogels-including hardness, springiness, cohesiveness, and adhesiveness-increased compared to pure-starch hydrogels. In addition, starch-borax DC hydrogels exhibited excellent self-healing and shape-recovery properties. These DC hydrogels, with a variety of excellent properties, have potential applications in agricultural, biomedical, and industrial fields.