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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