There is a huge requirement of elastomers for use in tires, seals, and shock absorbers every year worldwide. In view of a sustainable society, the next generation of elastomers is expected to combine outstanding healing, recycling, and damage‐tolerant capacities with high strength, elasticity, and toughness. However, it remains challenging to fabricate such elastomers because the mechanisms for the properties mentioned above are mutually exclusive. Herein, the fabrication of healable, recyclable, and mechanically tough polyurethane (PU) elastomers with outstanding damage tolerance by coordination of multiblock polymers of poly(dimethylsiloxane) (PDMS)/polycaprolactone (PCL) containing hydrogen and coordination bonding motifs with Zn2+ ions is reported. The organization of bipyridine groups coordinated with Zn2+ ions, carbamate groups cross‐linked with hydrogen bonds, and crystallized PCL segments generates phase‐separated dynamic hierarchical domains. Serving as rigid nanofillers capable of deformation and disintegration under an external force, the dynamic hierarchical domains can strengthen the elastomers and significantly enhance their toughness and fracture energy. As a result, the elastomers exhibit a tensile strength of ≈52.4 MPa, a toughness of ≈363.8 MJ m−3, and an exceptional fracture energy of ≈192.9 kJ m−2. Furthermore, the elastomers can be conveniently healed and recycled to regain their original mechanical properties and integrity under heating.

Spider silk is one of the most robust natural materials, which has extremely high strength in combination with great toughness and good elasticity. Inspired by spider silk but beyond it, a healable and recyclable supramolecular elastomer, possessing superhigh true stress at break (1.21 GPa) and ultrahigh toughness (390.2 MJ m−3), which are, respectively, comparable to and ≈2.4 times higher than those of typical spider silk, is developed. The elastomer has the highest tensile strength (ultimate engineering stress, 75.6 MPa) ever recorded for polymeric elastomers, rendering it the strongest and toughest healable elastomer thus far. The hyper‐robust elastomer exhibits superb crack tolerance with unprecedentedly high fracture energy (215.2 kJ m−2) that even exceeds that of metals and alloys, and superhigh elastic restorability allowing dimensional recovery from elongation over 12 times. These extraordinary mechanical performances mainly originate from the meticulously engineered hydrogen‐bonding segments, consisting of multiple acylsemicarbazide and urethane moieties linked with flexible alicyclic hexatomic spacers. Such hydrogen‐bonding segments, incorporated between extensible polymer chains, aggregate to form geometrically confined hydrogen‐bond arrays resembling those in spider silk. The hydrogen‐bond arrays act as firm but reversible crosslinks and sacrificial bonds for enormous energy dissipation, conferring exceptional mechanical robustness, healability, and recyclability on the elastomer.

The covalent functionalization of 2D crystals is an emerging route for tailoring the electronic structure and generating novel phenomena. Understanding the influence of ligand chemistry will enable the rational tailoring of their properties. Through the synthesis of numerous ligand-functionalized germanane crystals, we establish the role of ligand size and electronegativity on functionalization density, framework structure, and electronic structure. Nearly uniform termination only occurs with small ligands. Ligands that are too sterically bulky will lead to partial hydrogen termination of the framework. With a homogeneous distribution of different ligands, the band gaps and Raman shifts are dictated by their relative stoichiometry in a pseudolinear fashion similar to Vegard's law. Larger and more electronegative ligands expand the germanane framework, thereby lowering the band gap and Raman shift. Simply by changing the identity of the organic ligand, the band gap can be tuned by ∼15%, highlighting the power of functionalization chemistry to manipulate the properties of single-atom thick materials.

Since the first discovery of spontaneous emulsification, the process has remained uncontrollable for centuries leading to unstable emulsion droplets with limited uses. Herein, by in situ observation it was found that uniform water-in-oil (W/O) nanoemulsion droplets can be spontaneously formed and selforganized during solvent evaporation. Amphiphilic bottlebrush block copolymers are strongly adsorbed at the water/oil interface to stabilize the droplets, and their rod-like molecular conformation enables good control of the droplet spherical curvature. After solvent removal, solidified thin films or microparticles with hexagonal closest packed nanopore arrays are produced in one-step templated by the ordered W/O emulsions. The pore diameter is precisely tunable in a wide range (160 ≤ D ≤ 395 nm) by changing the spherical curvature of the water droplets dependent on the degree of polymerization of the bottlebrush block copolymer (BBCP) (89 ≤ DP ≤ 151). The well-ordered porous structures give rise to full-spectrum structural colors. This work provides a general method for scalable production of well-ordered porous materials with greatly reduced energy consumption.

Magnetic materials with excellent performances are desired for functional applications. Based on the high-entropy effect, a system of CoFeMnNiX (X = Al, Cr, Ga, and Sn) magnetic alloys are designed and investigated. The dramatic change in phase structures

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A series of high entropy alloys (HEAs), Al x NbTiMoV, was produced by a vacuum arc-melting method. Their microstructures and compressive mechanical behavior at room temperature were investigated. It has been found that a single solid-solution phase with a body-centered cubic (BCC) crystal structure forms in these alloys. Among these alloys, Al 0.5 NbTiMoV reaches the highest yield strength (1,625 MPa), which should be attributed to the considerable solid-solution strengthening behavior. Furthermore, serration and crackling noises near the yielding point was observed in the NbTiMoV alloy, which represents the first such reported phenomenon at room temperature in HEAs.

Stretchable conductive elastomers play an irreplaceable role in flexible electronic devices. However, stretchable conductive elastomers are usually soft and susceptible to damage. In this study, inspired from skin, highly stretchable and elastic conductive elastomers integrated with damage resistance, damage tolerance, and healability are fabricated by loading ionic liquids (ILs) within the polyurethane (PU) elastomers of the multiblock polymers of poly(dimethylsiloxane) (PDMS)/polycaprolactone (PCL) coordinated with Zn 2+ ions. The mechanically robust conductive elastomer, with a tensile strength of ∼15.2 MPa and a stretchability of ∼2668%, has a satisfactory ionic conductivity of 2.9 × 10 −4 S cm −1 . The conductive elastomer exhibits exceptional strain-adaptive stiffening, with an ∼100-fold increase in modulus when being fully stretched. The strain-adaptive stiffening endows the elastomer with excellent damage resistance. Meanwhile, the conductive elastomer has a record-high fracture energy of ∼33.8 kJ m −2 . The notched conductive elastomer can prevent the propagation of the notch up to a strain of ∼2400%. The exceptional strainadaptive stiffening and damage tolerance originate from the in situ formed phase-separated domains, which are deformable and disintegrable under an external force to significantly strengthen the elastomer and dissipate energy. Furthermore, the conductive elastomer can be conveniently healed under heating to restore its original conductivity and mechanical properties.