Polymeric materials combining good mechanical performances with self-healing ability and malleability have attracted dramatic attention, but it presently remains a challenge for the facile fabrication of such high-performance materials, not to mention the atomic-level characterization for understanding the molecular origin of the macroscopic properties. Herein, we proposed a facile strategy to fabricate a dual-cross-linked poly­(n-butyl acrylate) polymer material, in which the self-complementary quadruple hydrogen bonding interactions between 2-ureido-4­[1H]-pyrimidinone (UPy) dimers were utilized as the dynamic sacrificial cross-linkages, and thus to enhance the mechanical strength and toughness. The hydrogen bonding interactions between UPy dimers in such synthetic cross-linked polymer material were revealed in detail by selective saturation double-quantum (DQ) solid-state NMR spectroscopy under ultrafast magic-angle-spinning beyond 60 kHz. In the meantime, the self-healing capability and recyclability were achieved by utilizing dynamic fast boronic ester transesterification at an elevated temperature. A novel symmetrical diboronic ester cross-linker was developed and employed to enhance the probability of bornoic ester transesterification at an elevated temperature. The boronic ester transesterification was verified on a small molecular model and polymer materials by solution 1H NMR spectroscopy and swelling experiments, respectively, and the cross-linking structure of polymer materials was addressed by low-field proton multiple-quantum NMR spectroscopy and T 2 relaxometry. Overall, it is well demonstrated that a combination of diboronic ester bonds and UPy dimers as the chemical and physical cross-linkage, respectively, can impart the rubbery materials with enhanced mechanical stiffness and toughness, good healing and recycling efficiency, and elucidation of the structure–property relationship here can further provide piercing insights into the development of high-performance polymeric materials.

Electrically induced enormous magnetic anisotropy in Terfenol-D/lead zinc niobate-lead titanate multiferroic heterostructures J. Appl. Phys. 112, 063917 (2012) d0 ferromagnetism in undoped n and p-type In2O3 films Appl. Phys. Lett. 101, 132417 (2012) Microstructural and ferromagnetic resonance properties of epitaxial nickel ferrite films grown by chemical vapor deposition Appl.Surface and ultrathin-film magnetocrystalline anisotropy in epitaxial fee Fe thin films grown on room-temperature Cu( 100) single crystals has been investigated, in situ, by the combined surface magneto-optical Kerr effects (SMOKE). In polar, longitudinal, and transverse Kerr effects, the direction of the applied magnetic field must be distinguished from the direction of magnetization during the switching process. For arbitrary orientations of the magnetization and field axis relative to the optical scattering plane, any of the three Kerr effects may contribute to the detected signal. A general expression for the normalized light intensity sensed by a photodiode detector, involving all three combined Kerr effects, is obtained both in the ultrathin-film limit and for bulk, at general oblique incidence angles and with different orientations of the polarizer, modulator, and analyzer. This expression is used to interpret the results of fee Fe/Cu( 100) SMOKE measurements. For films grown at room temperature, polar and longitudinal Kerr-effect magnetization loops show that the easy axis of magnetization rotates from the (canted) out-of-plane direction to the in-plane direction at a thickness of about 4.7 monolayers. Transverse Kerr-effect measurements indicate that the in-plane easy axes are

Interfacial silyl ether networks can reshuffle the topological structure upon trans-oxyalkylation reactions, enabling malleability and recyclability to organic/inorganic hybrid vitrimers.

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It remains a huge challenge to create advanced elastomers combining high strength and great toughness. Despite enhanced strength and stiffness, elastomeric nanocomposites suffer notably reduced extensibility and toughness. Here, inspired by the concept of sacrificial bonding associated with many natural materials, a novel interface strategy is proposed to fabricate elastomer/graphene nanocomposites by constructing a strong yet sacrificial interface. This interface is composed of pyridine-Zn(2+) -catechol coordination motifs, which is strong enough to ensure uniform graphene dispersion and efficient stress transfer from matrix to fillers. Moreover, they are sacrificial under external stress, which dissipates much energy and facilitates chain orientation. As a result, the strength, modulus, and toughness of the elastomeric composites are simultaneously strikingly enhanced relative to elastomeric bulk. This work suggests a promising methodology of designing advanced elastomers with exceptional mechanical properties by engineering sacrificial bonds into the interface.

This research aims to investigate the influence of the slag basicity from 1.40 to 1.83 on dephosphorization of the hot metal with a CaO-FeO-SiO 2 -MgO-Al 2 O 3 molten slag at the low temperature of 1653 K. The results indicated that the dephosphorization ratio was increased with the increase of basicity. Even at the low basicities of 1.73 and 1.83, the dephosphorization ratios can be as high as 77.3 and 80.7%, respectively. With the increase of basicity, the contents of P 2 O 5 and total iron in the slag were increased, whereas the content of MnO was decreased. The distribution ratio of phosphorus (L P ) was expressed as log L P = 19.4L − 6381 T + 5.244 + log f P + 5 4 log P (O2) . The L P values calculated by the present method are well consistent with the measurement values. Besides, the dark grey phase B and the light grey phase D could be considered as the phosphorus-rich phases containing C 2 S solid particles.

The influence of temperature on the dephosphorization of hot metal at the low temperature range of 1300–1450 °C with the slag of the low basicity (CaO/SiO2) of about 1.8 is investigated using high‐temperature laboratorial experiments. The results show that with increasing temperature, the phosphorus contents in hot metal decrease first and then increase. The phosphorus can be removed from the initial content of 0.246% to the final content of 0.066% with the highest dephosphorization ratio of 73.2% at 1375 °C. The P2O5 content in slag increases first and then decreases. When the actual dephosphorization temperature is 1350–1375 °C being about 60 °C higher than the conversion temperature of decarbonization and dephosphorization, a very high LP of about 25 can be obtained. Moreover, the dephosphorization slag at the temperature from 1300 to 1400 °C is mainly comprised of three mineralogical phases: phosphorus‐rich, metal oxide (RO), and CaO–FeO–SiO2 phases. When the temperature is increased to 1425 and 1450 °C, the dephosphorization slag is mainly comprised of liquid slag containing Ca3(PO4)2 and RO phase.

Nature embraces an intriguing strategy to create high-performance biomaterials, such as spider silk which presents an unparalleled combination of stiffness, tensile strength, and toughness via hierarchical structures. However, to fabricate synthetic polymers with such excellent properties remains a challenging task. Inspired by the integration of multiblock backbone and densely H-bonding assemblies in spider silk as well as the delicate iron−catecholate complexes in mussel byssus, we proposed a novel molecular design with multifunctional block modules to obtain polymer materials that exhibit excellent mechanical property, self-healing ability, and reprocessability. It was achieved by introducing reversible iron−catechol (DOPA− Fe 3+ ) cross-links and quadruple H-bonds bearing 2-ureido-4-[1H]-pyrimidinone (UPy) dimers as multifunctional blocks into a segmented polyurethane backbone with urethane blocks and semicrystalline polycaprolactone (PCL) blocks. These two types of dynamic cross-linking knots served as the sacrificial bonds to dissipate energy efficiently under external stress burden, endowing the dual physical cross-linked networks with increased toughness and breaking elongation. Moreover, the DOPA−Fe 3+ complexes could increase the crystallization of PCL, leading to remarkably enhanced Young's modulus and tensile strength. Solid-state NMR revealed the formation of quadruple H-bonds in UPy dimers and the presence of DOPA−Fe 3+ complexes, which restricted the mobility of the mobile phase and enhanced the crystallinity of the PCL domain. This work provides a feasible way to develop bioinspired materials with self-healable and reprocessable features, in addition to balanced enhancement of both stiffness and toughness.