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Marine biological fouling has become a major obstacle to the development of marine industry. Silicone coating is becoming a promising environmental protection and antifouling material because of its nontoxic, harmless, and low surface energy. Herein, double-ended hydroxypropyl polydimethylsiloxane (PDMS) and polytetrahydrofuran (PTMG) were used as the main chain, 2-hydroxyethyl disulfide (HEDS) and dimethylglyoxime (DMG) were used as chain extenders, and Cu2+was used as the coordination metal. Then, by introducing silver nanoparticles (AgNPs), a AgNP hybrid silicone antifouling coating with spontaneous self-healing and long-term antifouling properties was constructed. The interaction of disulfide bonds, oxime urethane bonds, metal coordination bonds, and hydrogen bonds endowed a self-healing efficiency of 91.7%. As the reinforced effect of AgNPs, the mechanical properties of the coating could reach up to 2.75 MPa. The surface energy of the coating was controlled below 25 mJ·m–2, which had good dirt release performance and self-cleaning ability. Due to the excellent antibacterial activity of AgNPs, the resistance to marine bacteria Pseudomonas was up to 97.8%, which effectively inhibited the formation of biofilms. This work provided guidance for the development of marine antifouling coatings with self-healing, pollution-free, and long-term antifouling abilities.

The design and synthesis of conductive hydrogels with antifreezing, long-term stable, highly sensitive, self-healing, and reusable is a critical procedure to enable applications in flexible electronics, medical monitoring, soft robotics, etc. Herein, a novel zwitterionic composite hydrogel possessing antifreezing, fast self-healing performance, water retention, and adhesion was synthesized via a simple one-pot method. LiCl, as an electrolyte and antifreeze, was promoted to dissociate under the electrostatic interaction with zwitterions, resulting in the composite hydrogels with high electrical conductivity (7.95 S/m) and excellent antifreeze ability (−45.3 °C). Meanwhile, the composite hydrogels could maintain 97% of the initial water content after exposed to air (25 °C, 55% RH) for 1 week due to the presence of salt ions. Moreover, the active groups of zwitterions could form conformal adhesion between the composite hydrogels and skin, which was particularly crucial for the stable signal output of the sensor. The dynamic borate ester bonds, active group of zwitterions, and the hydrogen bond between different components could achieve rapid self-healing (2 h, self-healing efficiency to 97%) without any external intervention. Notably, the developed PBAS-Li (poly(vinyl alcohol) Borax/acrylamide/zwitterionic-LiCl) hydrogel not only succeeded in sensitively detecting human motions but also could precisely captured handwritings signals and subtle pulse waves on the neck and wrist. The above findings demonstrated the great potential of PBAS-Li hydrogels in the field of flexible electronic devices.

Astragali Radix(AR) is one of the most widely used traditional Chinese medicines (TCMs) for tonic, which can be divided into wild-simulated and cultivated AR according to its cultivation method. However, whether cultivated AR can replace wild-simulated AR has always been a concern.

Flexible conductive composites can be used as wearable strain sensors, which are widely used in the fields of new-generation robotics, electronic skin, and human detection. However, how to make conductive composites that simultaneously possess flexibility, stretchability, self-healing, and sensing capability is challenging research. In this work, we innovatively designed and prepared a silicone polymer conductive composite. MXenes and amino poly(dimethylsiloxane) were modified by small biomolecules via an esterification reaction and a Schiff base reaction, respectively. The modified MXenes are uniformly dispersed, which endows the composite with good electrical conductivity. The reversibility of multiple hydrogen bonds and imine bonds in the composite system makes it have ideal tensile properties and high-efficiency self-healing ability without external stimulation. The conductive composite containing 10 wt % A-MXenes showed an elongation of 81%, and its mechanical strength could reach 1.81 MPa. After repair, the tensile properties and the electrical conductivity could be restored to 98.4 and 97.6%, respectively. In addition, the conductive composite is further evaluated for the value of wearable strain sensors. Even after cut-healed processes, the conductive composite can still accurately detect tiny human movements (including speaking, swallowing, and pressing). This kind of self-healing MXene/PDMS elastomers based on the modification of small biomolecules has great potential as wearable strain sensors. This simple preparation method provides guidance for future multifunctional flexible electronic materials.

The hemihydrate calcium sulfate whisker (HCSW) was modified by γ‐(methacryloxy)propyl trimethoxy silane (KH570) and trimethylolpropane tris(3‐mercaptopropionate) via wet modification and thiol‐ene click reaction, and then the unmodified and modified HCSW were added into α, ω‐dihydroxy polysiloxane (DPS) matrix to prepare silicon rubber composites. After the dual‐surface modification, the surface of HCSW was transformed to hydrophobic, the hydration of whisker was obviously improved, and the whisker dispersed more evenly in the polymer. The mechanical properties, dynamic mechanical properties, and the medium resistance of the silicone rubber composite were compared. The tensile test shows that the silicone rubber shows better mechanical properties after adding the modified whiskers, among which HCSW‐KH570‐SH has the most significant reinforcement effect. Moreover, DPS/HCSW‐KH570‐SH shows the best medium resistance in toluene, gasoline, and water. The addition of modified whiskers can improve the storage modulus of silicone rubber significantly, while DMA and DSC show that the addition of modified whiskers can reduce the glass transition temperature of silicone rubber. The bound rubber indicates that the interface interaction between HCSW‐KH570‐SH and silicone rubber is the best. A new organic–inorganic hybrid material is synthesized. Surface modification of HCSW is carried out by wet modification and thiol‐ene click reaction, and the double‐surface modified HCSW is used as reinforcing material for DPS materials. The mechanical properties of DPS composites are significantly improved after adding HCSW.

The formation of reversible hydrogen bonds is a promising strategy for cross-linking organosilicon elastomers, which can yield the fascinating properties. Herein, we reported a new type of self-healing silicone rubber (hydrogen bond cross-linked silicone rubber, HBSR) cross-linked by the multiple hydrogen bonds with α,ω-aminopropyl poly(dimethylsiloxane) and ethylene carbonate based on the nonisocyanate reaction. The multiple hydrogen bonds between the carbonyl and imino groups as well as the generated hydroxyl groups were proved by the variable temperature Fourier transform infrared analysis. This ultimately produced a hydrogen bond cross-linked network of HBSR. The tensile strength of HBSR could reach to 0.52 MPa that was equal or even better than the conventional room-temperature vulcanized silicone rubber without fillers. The thermodynamic tests indicated that HBSR exhibited good thermal stability, which was not influenced by the generated hydroxyl groups. Moreover, the multiple hydrogen bonds led to a thermal-induced self-healing efficiency of 88.5% and good cyclic self-healing ability of HBSR. This study provided an alternative method to fabricate the self-healing silicone rubber with the hydrogen bond interactions. The type of silicone rubber might be applied into the soft robotics, wearable electronics, and stretchable circuit structure.

The choice of blood specimens is still disputable in metabonomic studies due to the great metabolic diversities of serum and plasma. In the present work, a proton nuclear magnetic resonance spectroscopy (NMR)-based metabonomic approach was introduced to explore metabolic differences between serum and plasma coupled with its application in the pathogenesis of chronic atrophic gastritis (CAG). As a result, 3 and 20 identified metabolites were applied to characterize the metabolic differences between serum and plasma, respectively, in control or CAG rats, which might be related to the effect of anticoagulants. Almost all the metabolic contents except lactate and β-glucose in serum samples were higher than those in plasma samples. Meanwhile, 12 serum and 11 plasma potential biomarkers were detected to relate to the formation of CAG by comparisons of the normal and CAG groups, respectively. Receiver operating characteristic analysis (ROC) also showed that serum specimens were clearly superior to plasma based on sensitivity of the diagnosis of CAG. The results showed that the combination of them could enhance the metabolic coverage related to the mechanism of CAG, which involves oxidative stress, energy failure, cell injury and death. Furthermore, selecting a serum specimen might be a good way to investigate the blood metabolome, especially under pathological states. This may favor the use of serum rather than plasma in NMR-based metabonomics.