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Materials able to regenerate after damage have been the object of investigation since the ancient times. For instance, self‐healing concretes, able to resist earthquakes, aging, weather, and seawater have been known since the times of ancient Rome and are still the object of research. During the last decade, there has been an increasing interest in self‐healing electronic materials, for applications in electronic skin (E‐skin) for health monitoring, wearable and stretchable sensors, actuators, transistors, energy harvesting, and storage devices. Self‐healing materials based on conducting polymers are particularly attractive due to their tunable high conductivity, good stability, intrinsic flexibility, excellent processability and biocompatibility. Here recent developments are reviewed in the field of self‐healing electronic materials based on conducting polymers, such as poly 3,4‐ethylenedioxythiophene (PEDOT), polypyrrole (PPy), and polyaniline (PANI). The different types of healing, the strategies adopted to optimize electrical and mechanical properties, and the various possible healing mechanisms are introduced. Finally, the main challenges and perspectives in the field are discussed.

require low-impedance at the electrodetissue interface to maintain efficient charge injection during stimulation. [4] The impedance of the electrode sites of neural probes steadily increases with time during implantation due to the immune system's response to the insertion of the probes into tissue. [5] Conducting polymers have been widely explored as coatings for stimulating neural probes to reduce the impedance at the electrode-tissue interface. [6,7] Among conducting polymers, poly(3,4ethylenedioxythiophene) (PEDOT) has significantly contributed to improving the electrical stability of neural probes due to its high conductivity, electrochemical stability under chronic exposure to biological environments, and compliant mechanical properties which provide a softer interface between brain tissue and stiff probes. [8][9][10] The stability of PEDOT coatings on the electrode sites of neural probes is critical for ensuring the long-term functionality of the neural device. [11] One major mode of PEDOT coating failure is through coating delamination or cracking. [12][13][14][15] The coating must be able to survive mechanical stresses, swelling, and electrode corrosion in order to be considered for use in clinical applications. [16] Substantial improvements in PEDOT stability have been achieved through tuning the polymerization parameters, accurately selecting dopants and solvents used for polymerization, and incorporating additives into the PEDOT film. [10,[17][18][19][20] Chronic stability of PEDOT-based recording neural electrodes has been extensively studied and reviewed. [8,19,[21][22][23][24][25][26][27][28][29] Studies of PEDOT coating stability under stimulation have been recently reviewed. [7,16,17] In one study, electropolymerized PEDOT, containing carbon nanotubes, on Pt microelectrodes was monitored over 3 months of soaking in phosphate buffered saline (PBS) with and without stimulation, and were reported to have stable impedance. [30] An in vivo study stimulated the Au electrode sites of a neural probe coated with PEDOT and carbon nanotubes for 1 h a day for 10 days (20 mA, 200 Hz). PEDOT demonstrated similar impedance values to Au electrode sites at the end of the study. [31] On the other hand, PEDOT doped with tetrafluoroborate (PEDOT:BF 4 ) electropolymerized on platinum iridium (PtIr) neural probes was implanted for 15 days, stimulated daily for 90 min (20 mA, 130 Hz) while monitoring the impedance. At the end of the implantation period, Resulting from its many unique properties, such as mechanical compliancy, electrochemical stability, and high conductivity, the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is a promising material for improving the stimulation efficiency of neural microelectrodes. The long-term electrochemical stability of penetrating PEDOT-coated electrodes undergoing high-frequency stimulation is not extensively studied in vivo and the inflammatory response of the brain to PEDOT-coated stimulating neural probes is not well understood. In this work, electropolymerized PE...

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The certain nitrate ester explosive has been tested by TG at the heating rates of 10, 15, 20, 25K•min-1. Basing on the TG experiment results the thermal decomposition activation energy has been calculated by the methods of Ozawa, KAS and iteration. And the thermal decomposition mechanism function of the explosive with 38 kinds of dynamic function was deduced by the method of integration. The results show that the thermal decomposition mechanism of the nitrate ester is chemical reaction mechanism. The thermal decomposition kinetic parameters such as average activation energy Ea and pre-exponential factor A are 133.23×103 J•mol-1 and 3.191×107 s-1 respectively.

Energetic composite materials (ECMs) are the basic materials of polymer binder explosives and composite solid propellants, which are mainly composed of explosive crystals and binders. During the manufacturing, storage and use of ECMs, the bonding surface is prone to micro/fine cracks or defects caused by external stimuli such as temperature, humidity and impact, affecting the safety and service of ECMs. Therefore, substantial efforts have been devoted to designing suitable self-healing binders aimed at repairing cracks/defects. This review describes the research progress on self-healing binders for ECMs. The structural designs of these strategies to manipulate macro-molecular and/or supramolecular polymers are discussed in detail, and then the implementation of these strategies on ECMs is discussed. However, the reasonable configuration of robust microstructures and effective dynamic exchange are still challenges. Therefore, the prospects for the development of self-healing binders for ECMs are proposed. These critical insights are emphasized to guide the research on developing novel self-healing binders for ECMs in the future.

LiNbO3:Yb3+/Er3+ nanocubes with the average diameter of approximately 500 nm were firstly applied in non-invasion optical temperature sensors. As increasing the annealing temperature, a two orders of magnitude enhancement of...

Room-temperature self-healing adhesives require more flexible polymer chains and weaker interactions, which are not conducive to good mechanical properties. Therefore, an energetic self-healing adhesive containing asymmetric alicyclic structures and multiple urea groups was designed. The asymmetric alicyclic structures could form loosely packed hard domains, and the irregular arrangement of multiple continuous urea groups could strengthen the physical cross-linking and improve the strengths of the hard domains. As a result, adhesives with improved mechanical properties (tensile strength and toughness) were obtained, and their dynamic adaptabilities and responsiveness required for self-healing at room temperature were maintained. The glycidyl azide polymer-based polyurethane (GPU) adhesive (GPU-3.0) exhibited excellent comprehensive performance in terms of toughness, healing efficiency, adhesion strength, and energy level. The maximum tensile strength and toughness of the energetic composite material (ECM, GPU/Al) prepared using GPU-3.0 and Al were 2.52 MPa and 2.45 MJ m–3, respectively. After 72 h at room temperature, the scratches on the GPU/Al surface were no longer observed and the mechanical properties were completely recovered. Therefore, the designed adhesive, which displays a high-efficiency room-temperature self-healing capacity and good mechanical properties, is applicable in self-healing ECM systems. This strategy should provide insights for use in improving the stabilities and safety of ECMs.