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The present paper is devoted to preparation of intrinsic self-healing polymeric materials used for structural applications. The authors introduced a novel healing chemistry based on dynamically reversible C–ON bonds, which imitates natural healing in living bodies without affecting their operations. To verify its feasibility, alkoxyamine moieties served as intermolecular links in polystyrene. Upon heating, covalent bond fission and radical recombination synchronously took place among alkoxyamine moieties. Cracked parts were thus reconnected repeatedly, without losing integrity and load bearing ability of the material even above T g.

Stimuli‐responsive polymers built by reversible covalent bonds used to possess unbalanced mechanical properties. Here, a crosslinked polyurethane containing aromatic pinacol as a novel reversible CC bond provider is synthesized, whose tensile strength and failure strain are tunable from 27.3 MPa to as high as 115.2 MPa and from 324% to 1501%, respectively, owing to the relatively high bond energy of the CC bond of pinacol as well as the hydrogen bond between hard segments and semicrystalline soft segments. Moreover, the dynamic equilibrium of pinacol enables self‐healing and recycling of the polymer. Interestingly, the dynamic exchange among macromolecules, for the first time, successfully cooperates with solid‐state drawing that applies to thermoplastics, realizing strengthening of thermoset. Meanwhile, the radicals derived from homolysis of pinacol can repeatedly initiate polymerization of vinyl monomers. The fruitful outcomes of this work may create a series of promising new techniques.

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A novel strategy for developing homogeneous reversibly interlocking polymer networks (RILNs) with enhanced mechanical properties and underwater self-healing ability is proposed. The RILNs are prepared by the topological reorganization of two preformed cross-linked polymers containing reversible catechol−Fe 3+ coordinate bonds and imine bonds and exhibit enhanced mechanical properties, superior underwater self-healing effect within a wide pH range, and water-assisted recycling ability through synergetic action between the reversible catechol−Fe 3+ and imine bonds. At higher pH values, the catechol−Fe 3+ coordinate bonds are responsible for self-healing, while the imine bonds maintain the stability of the materials. In neutral water, the imine bonds mainly account for self-healing, and hydrogen bonds and entanglements between the two networks prevent the material from collapsing. Under a lower pH value, intermolecular hydrogen bonds and entanglements contribute to self-healing. The outcomes of this work provide a new idea for developing robust multifunctional underwater self-healing materials.

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A strategy for developing self-healing crosslinked polymer with alkoxyamine is proposed, which ensures air resistance even at higher homolysis temperature.