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The self-healing property of biological tissues gives humans inspiration to endow artificial synthetic materials with self-healing functions. Herein, we report a thermoplastic elastomer that can be self-repaired in a short time, which uses dual dynamic bonds (hydrogen bonds and disulfide bonds) coupled to realize its self-healing function through the rapid conversion of dynamic hydrogen bonds between the hard and soft segments, as well as the dynamic bonding and dissociation of disulfide bonds. Furthermore, the maximum tensile strength and strain of the elastomer can reach 17.4 MPa and 3780%, respectively, and the maximum self-healing rate is close to 100% (temperature: 90 °C, time: 5 h). The arrays’ arrangement and reversibility of hydrogen bonds endow the elastomer with high toughness and self-healing properties and thus solve the problem that ordinary polymers cannot self-heal.

In this article, polyvinylpyrrolidone (PVP) was used for the noncovalent modification on the surface of graphene. Compared with covalent modification, this method maintained the original structure of graphene layers, thereby maximizing the original properties of graphene. The π–π noncovalent bond was formed between PVP and graphene by X-ray photoelectron spectroscopy analysis, indicating that PVP successfully modified graphene. The thickness of graphene layer was measured by atomic force microscopy, which showed that the distance between graphene layers was increased by 5–6 nm, and the stability of the modified graphene in N, N-dimethylformamide was remarkably improved. The obtained composite coating by combination of the modified graphene and the epoxy resin was subjected to electrochemical impedance test to obtain the best anticorrosive effect of the coating with the graphene content of 0.3 wt%. The results showed that the addition of graphene to the epoxy resin could effectively improve the anticorrosive effect. Meanwhile, the good electrical conductivity allowed the electrons which lost from the substrate to led to air or saline rapidly, thereby reducing the combination of iron ions with oxygen and the generation of corrosion products (iron oxides).

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Although a wide range of self-healing materials have been reported by researchers, it is still a challenge to endow exceptional mechanical properties and shape memory characteristics simultaneously in a single material.

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Although self-healing elastomers have been developed in a great breakthrough, it is still a challenge to develop one kind of material that can respond to the fracture instantly even though this characteristic plays an essential role in emergency circumstances. Herein, we adopt free radical polymerization to construct one polymer network equipped with two weak interactions (dipole–dipole interaction and hydrogen bonding). The elastomer we synthesized has a high self-healing efficiency (100%) and a very short healing time (3 min) in an air atmosphere, and it can also self-heal in seawater, showing an ideal healing efficiency of >80%. Additionally, on account of its high elongation (>1000%) and antifatigue capacity (no rupture after loading–unloading 2000 times), the elastomer can be utilized in a wide range of applications, including e-skin and soft robot fields.