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A three‐dimensional conductive nanocomposite with an ordered conductive network and low percolation threshold has been successfully prepared by blending graphite nanosheets (GNs) with polyethylene on a two‐roll mill. The conductive nanosheets orient intensively in the composite, leading to highly anisotropic properties. The nanocomposite with the fraction of conductive nanosheets closest to the percolation threshold possesses a sharp positive pressure coefficient of resistivity, in which the abrupt transition can be attributed to compressive‐stress‐induced deformation of the conductive network. Such piezoresistive effects depend strongly on filler morphology, filler spatial arrangement, and filler concentration.

Metal-organic frameworks (MOFs) are a new type of functional material that is self-assembled by metal ions and organic ligands. In this paper, a bimetal-organic framework was synthesized and stripped into two-dimensional nanosheets structure via an ultrasonic method. We coated the UMOFNs (ultrathinning MOFs into two-dimensional nanosheets) on AgPO nanoparticles to obtain AgPO@UMOFNs core-shell photocatalysts. Under visible-light irradiation, the degradation of phenol was 100% within 16 min, and the degradation of biphenyl A was 98.9% within 20 min via AgPO@UMOFNs (5 wt %). These values were 1.6- and 1.8-times higher than AgPO, respectively. The activity of the AgPO@UMOFNs increased due to the synergistic effects. The π-π bonds of the organic ligands and weak interactions between UMOFNs and AgPO collectively promote charge transfer. In addition, matching energy-level structures and a sufficiently large contact area accelerate the separation of the photogenerated charges and improve the activity. This remarkably improves the photocatalytic activity.

A novel functional tweezer based on uracil-appended glycyrrhetinic acid with excellent gelation ability was synthesized, and the gel could transform to sol by F(-) and Hg(2+).

In this study, the nylon 6/foliated graphite (FG) electrically conducting nanocomposites with a low percolation threshold of less than 0.75 vol % have been prepared via an in situ polymerization approach in the presence of FG nanosheet filler. Based on laser counting, scanning electron microscopy, transmission electron microscopy, and X-ray diffraction characterization techniques, the structures and morphologies of the nanoscale filling particles and the resulting nanocomposites were examined. Using percolation theory, the conductivity behavior of the nanocomposite samples were modeled and analyzed. Through the use of mean-field and excluded volume approaches, it was demonstrated that the experimentally observed percolation threshold values could be approximately estimated, and a correlation between the percolation threshold and the aspect ratio of FG particles could be quasi-quantitatively established. Also, preliminary studies on the effects of FG nanosheets on the thermal properties of the host nylon 6 were performed.

The conjugate of oleanlic acid with adenine was synthesized and it could be gelled in mixed solvents of THF and water, but no gel was formed in the single organic solvent. The self-aggregation behaviour and physical properties of the organogel were characterized by 1 H NMR, FT-IR, and scanning electron microscopy. The morphology and the stability of the gel were remarkably affected by the uracil derivative through destroying hydrogen-bonding.

Sodium glycyrrhetinate, a simple triterpenoid derivative, was found to form a hydrogel with dipole-dipole interaction of sodium carboxylates as the main driving force. The hydrogel showed properties in selective dye adsorption and sustainable release. Fig. 1 Chemical structures of GA (1) and sodium glycyrrhetinate (2).