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The preparation of natural rubber (NR)–silica (SiO 2 ) elastomeric composites with excellent mechanical properties along with better self-healing ability remains a key challenge. Inspired by the energy dissipation and repairability of sacrificial bonds in biomaterials, a strategy for combining covalent and noncovalent sacrificial networks is engineered to construct a dual hybrid network. Here, the approach used to fabricate the composites was self-assembly of NR, bearing proteins and phospholipids on its outer bioshell, with SiO 2 via metal-ion-mediated heteroaggregation effected by reversible electrostatic and H-bonds. Further, covalent cross-links were incorporated by a silane coupling agent, bis [3-(triethoxysilyl) propyl] tetrasulfide. The intrinsic self-healing ability of the composite at the molecular level was studied by broadband dielectric spectroscopy that unraveled the mechanism of the healing process. The synergistic effect between the molecular interdiffusion of the cross-linked NR chains and the electrostatic and H-bonding interactions imparted an exceptional self-healing characteristic to the liquid–liquid-mixing-prepared NR–SiO 2 composites with improved mechanical performance. Specifically, the segmental relaxation dynamics of the healed composite was largely restricted due to increased number of ion–dipole interactions and S–S cross-links at the junction of the cut surface. We envisage that this extraordinary healing property, unreported yet, would be of great importance toward the design of novel NR–SiO 2 elastomeric hybrids with superior mechanical properties.

Two-dimensional (2D) carbon nanomaterials possessing promising physical and chemical properties find applications in high-performance energy storage devices and catalysts. However, large-scale fabrication of 2D carbon nanostructures is based on a few specific carbon templates or precursors and poses a formidable challenge. Now a new bottom-up method for carbon nanosheet fabrication using a newly designed anisotropic carbon nanoring molecule, CPPhen, is presented. CPPhen was self-assembled at a dynamic air-water interface with a vortex motion to afford molecular nanosheets, which were then carbonized under inert gas flow. Their nanosheet morphologies were retained after carbonization, which has never been seen for low-molecular weight compounds. Furthermore, adding pyridine as a nitrogen dopant in the self-assembly step successfully afforded nitrogen-doped carbon nanosheets containing mainly pyridinic nitrogen species.

Homogeneous dispersion of silica nanoparticles (SiO2 NPs) in natural rubber (NR) is a key challenge for engineering high-performance nanocomposites and elucidation of their structure on a molecular basis.

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