Stretchable and autonomously self-healable elastomers with wide-ranging tunable mechanical properties have attracted increasing attention in various industries. To date, it continues to be a huge challenge to synthesize selfhealing elastomers integrating extreme stretchability, relatively high mechanical modulus, and autonomous and rapid selfhealing capability. Herein, we propose a novel covalent/ supramolecular hybrid construction strategy, in which the covalent cross-links are responsible for providing high modulus and elasticity, while supramolecular cross-links realize extreme stretchability and rapid self-healing under room temperature depending on the ultrafast exchange kinetics of metal−ligand motifs and multicoordination modes. The representative polyurea hybrid elastomer, CSH-PPG-Zn-0.25, can be stretched more than 180× its original length with the highest Young's modulus (1.78 ± 0.08 MPa) among reported ultrastretchable materials. CSH-PPG-Zn-0.25 can fully restore mechanical properties of completely cut samples within 3 h. Note that the healing process can take place under a low temperature of −20 °C and unaffected by surface aging and atmospheric moisture. Merely tailoring the molar ratio of metal/ligand actualizes wide-ranging tunability of mechanical and dynamic properties, such as Young's modulus (from 1.71 ± 0.08 MPa to 5.56 ± 0.22 MPa), maximum tensile strength (from 0.32 ± 0.03 MPa to 4.42 ± 0.23 MPa), strain at break (from >18000% to 630 ± 27%), and storage modulus, ascribed to the increase of cross-linking density and formation of stiff ionic clusters. On the basis of the different material characteristics, two typical elastomers are employed, respectively, as flexible and self-healable conductor and self-healable automotive paint. Benefiting from the fantastic antiaging and low-temperature healing features of CSH-PPG-Zn-0.25, the prepared Ag-NWs/ CSH-PPG-Zn-0.25 conductor can even regain its conductive function below zero. CSH-PPG-Zn-0.50 material, meeting the strict mechanical requirements of automotive paints, is able to thoroughly eliminate the surface scratches and recover anticorrosion function in the local damaged region under the atmospheric environment.

A study of the decomposition behaviour for Ammonium Perchlorate(AP) was carried out by differential thermal analysis and the two decomposition peaks were observed. The high temperature peak was found to shift to lower temperatures, but the corresponding shift in the low temperature peak was smaller due to the effect of nanometer metal powders. Results shows that Cu and NiCu nanopowders decreased both the high and low decomposition temperature, while Ni and Al nanopowders just decreased the high decomposition temperature and increased the low decomposition temperature. Metal micron‐sized powders show catalytic effects on the thermal decomposition of AP, but their effects are less than that of nanometer metal powders. With the increase in content, nanometer metal powders enhanced their catalytic effect on the high temperature decomposition of AP, however their effect was weakened on the low temperature decomposition.

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Advanced rechargeable lithium-based batteries have a profound effect on our global society and polymer materials are one of the key components of these batteries. The key roles of polymers applied in battery technology are presented in terms of binders, package coatings, separators, and electrolytes. However, the loathsomely structural changes during repeated charge/discharge processes result in the mechanical fracture problems of polymers inside batteries, which significantly reduce the cycling lifetimes. The use of intrinsic self-healing polymers as substitutes is one of the most favored strategies for reviving lithium-based batteries since self-healing polymers spontaneously eliminate the mechanical cracks or damages and result in greatly enhanced electrochemical performances. In this review, we first introduce the advances and working mechanism of intrinsic self-healing polymers. Then, we discuss the opportunities and challenges in the development of advanced lithium-based batteries with Si, Li-metal, S electrodes, and polymer electrolytes, respectively, and summarize the up-to-date key progress in intrinsic self-healing polymers for solving the above-mentioned challenges. Finally, we propose some designing principles of desired intrinsic self-healing polymers from the perspectives of basic structures, ionic conductivities, mechanical properties, chemical interactions, and the self-healing capabilities.

In the field of energy storage, layered double hydroxides (LDHs) have aroused researchers' extensive attentions because of their low cost, high theoretical specific capacitance (SC), and adjustable interlayer structure. Notably, the appearance of single-layer or few-layer LDHs nanosheets has addressed the puzzle of large wall thickness and shows a large specific surface area which produces more active sites. However, the cyclic stability of the LDHs nanosheets has been hindered, which result from their poor conductivity, weak structural stability and natural stacking, so the usefulness of them is limited in practice. In this work, exfoliated twodimensional (2D) MXene (F-MXene)/exfoliated 2D ZnMnNi LDH (F-ZnMnNi LDH) van der Waals heterostructures were successfully fabricated by using electrostatic self-assembly between negatively titanium carbide F-MXene nanosheets and positively charged F-ZnMnNi LDH nanosheets. The as-prepared 2D/2D van der Waals heterostructures integrate the advantages of F-MXene and F-ZnMnNi LDH, including outstanding electron conductivity, stable structure, and superior redox activity. Accordingly, the as-prepared sample exhibits ultrahigh SC of 2065 F/g at a scan rate of 5 mV/s and remarkable cycling stability with capacitance retention of 99.8% after 100 000 cycles at a current density of 1 A/g.