A novel capacitor with high dielectric constant (ε) has been developed by blending poly(vinylidene fluoride) (PVDF) with polyamide (PA11). The blends show high dielectric constants (εblend = 40), which give better frequency stability (1 MHz), and excellent mechanical properties. Based on certain volume fractions, the measured dielectric constants (εblend) were found to exceed those of the corresponding polymers, in contrasted to conventional composites, where εpolymerA < εcomposite < εpolymerB. SEM investigations suggest that the enhanced dielectric behavior originates from significant interfacial polymer‐polymer interactions. DSC and XRD demonstrate that blending PA11 with PVDF affects the crystalline behavior of each component. However, the PA11/PVDF blends exhibit a slightly high dielectric loss (tanδ ≈ 0.17), which is a great disadvantage to a capacitor. Adding a copolymer of styrene and maleic anhydride decreased the dielectric loss (tanδ ≈ 0.057) and increased the dielectric constant (εblend = 60). Our findings suggest that the high‐ε polymeric blends created represent a novel type of material that is flexible and easy to process, of relatively high dielectric constant, of high breakdown strength and, moreover, is suited to applications in flexible electronics.magnified image

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Microcellular polypropylene (PP) was prepared through chemical microcellular injection under different processing parameters. The effects of cell structure parameters on the mechanical properties of PP materials were analyzed by the microsphere model. The results show that the mechanical properties of microcellular PP with a smaller cell size and more uniform size distribution were enhanced. The relationship between the mechanical properties and cell structure parameters correlated well with the theoretical model.

Development of three-dimensional nano-architectures on current collectors has emerged as an effective strategy for enhancing rate capability and cycling stability of the electrodes. Herein, a novel type of Ni3V2O8 nanowires, organized by ultrathin hierarchical nanosheets (less than 5 nm) on Ti foil, has been obtained by a two-step hydrothermal synthesis method. Studies on structural and thermal properties of the as-prepared Ni3V2O8 nanowire arrays are carried out and their morphology has changed obviously in the following heat treatment at 300 and 500 °C. As an electrode material for lithium ion batteries, the unique configuration of Ni3V2O8 nanowires presents enhanced capacitance, satisfying rate capability and good cycling stability. The reversible capacity of the as-prepared Ni3V2O8 nanowire arrays reaches 969.72 mAh·g−1 with a coulombic efficiency over 99% at 500 mA·g−1 after 500 cycles.