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An experimental study was conducted to improve the electrical insulation of epoxy resin. The effects of boehmite, γ-alumina and α-alumina nanoparticles on the volume resistivity, dielectric strength and glass transition temperature of epoxy nanocomposites were investigated. The results showed that α-alumina nanoparticles displayed obvious advantages in enhancing electrical insulation performance of epoxy nanocomposites, compared to boehmite and γ-alumina nanoparticles. The direct current volume resistivity and breakdown strength of epoxy nanocomposite with 2.0 wt% α-alumina nanoparticles was improved to 2.2 × 10 18 Ω cm and 76.1 kV mm −1 respectively. And these improved values of electrical insulation properties are much higher than these of epoxy nanocomposites reported in previous studies. The main reason of these improvements may be that the epoxy/α-alumina interaction zone was enhanced by crosslink. [ABSTRACT FROM AUTHOR]

Abstract: Pea starch nanocrystals (PSN) dispersion containing nanocrystals in a range of 30–80nm was prepared from native pea starch (NPS) granules by acid hydrolysis. Two series of films were prepared by blending poly(vinyl alcohol) (PVA) with NPS and PSN, respectively. The effects of NPS and PSN on the structure and properties of the resulting films were comparatively investigated by FTIR, XRD, SEM, and testing of light transmittance, tensile, and moisture uptake. The light transmittance (Tr), tensile strength (σ b), and elongation at break (ε b) of the PVA/NPS films were lower than that of PVA film and decreased with an increase in NPS content. However, the PVA/PSN nanocomposite films containing 5 and 10wt% of PSN content exhibited improved physical properties over the PVA film. The PVA/PSN films showed higher Tr, σ b, and ε b, and lower moisture uptake (Mu) than the corresponding PVA/NPS films with the same component ration. For example, the values of Tr, σ b, ε b, and Mu of the PVA/PSN film containing 10wt% of PSN content were 91%, 40MPa, 734% and 71%, respectively; while those of the corresponding PVA/NPS film were 69%, 35MPa, 579% and 73%, respectively. The results revealed that PSN, comparing with NPS, had much smaller sizes and dispersed more homogeneously in PVA matrix, resulting in stronger interactions with PVA. New applications of native pea starch and its nanocrystals as low-cost fillers were explored in this work, and PSN exhibited greater potential than NPS to improve the properties of PVA-based composites. [Copyright &y& Elsevier]

[Display omitted] • Piezocatalytic activity of Bi 2 WO 6 was potently improved by doping Ag 2 O. • Piezocatalytic removal rate of CIP reached 93.44 % ± 0.34 % using Ag 2 O/Bi 2 WO 6 composite. • Ag 2 O/Bi 2 WO 6 showed bright application prospects in environmental rehabilitation. Bi 2 WO 6 , an important semiconductor material, has been widely used in the catalytic degradation of organic wastewater in recent years. However, Bi 2 WO 6 owns the low band gap energy, the recombination of the produced e−-h+ pairs expected to be fast, which leads to undesirable degradation effects. In order to improve its piezocatalytic ability, this paper combined the semiconductor material Bi 2 WO 6 with Ag 2 O to form Ag 2 O/Bi 2 WO 6 piezoelectric catalysts, which was characterized and its removal effect on ciprofloxacin (CIP) was discussed. According to the analyses, the reaction rate constant for the piezocatalytic removal of CIP in the company of 5 % composite ratio of Ag 2 O/Bi 2 WO 6 was about 1.40 and 4.87 times higher than it was when Bi 2 WO 6 and piezocatalytic technology were used alone. By exploring the experimental principle, the increased piezocatalytic activity of Ag 2 O/Bi 2 WO 6 was found to be due to the creation of Z-scheme heterojunction, which could efficiently separate the e−-h+ pairs. Reuse experiments were also carried out, and the results showed that it has good reusability and stability in piezocatalysis. In summary, Ag 2 O/Bi 2 WO 6 has good piezocatalytic activity for the removal of CIP. [ABSTRACT FROM AUTHOR]

Abstract: We herein report the synthesis of ternary nanocomposites consisting of polyaniline (PANI), activated carbon, and TiO2(B) components, which involves the preparation of activated carbon/TiO2(B) nanowires (ACTB) using sonochemical–hydrothermal method, and their subsequent composites with PANI via in situ polymerization. The morphology and structure of ACTB/PANI ternary nanocomposites are characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR) and X-ray diffraction (XRD). Morphology analysis shows that the porous network layer of PANI homogeneously coated on the outer surface of ACTB support. The electrochemical properties of the ternary nanocomposite as the electrode material for electrochemical capacitors are examined by cyclic voltammetry and galvanostatic charge/discharge test in an organic electrolyte (1.0M LiClO4 in propylene carbonate). The results show that the ternary nanocomposites have a specific capacitance as large as 286Fg−1 in the potential range from −3 to 3V (vs. SCE) at a charge–discharge current density of 1.0Ag−1, which is a significant improvement compared to those of the three separate components, demonstrating that the ACTB/PANI nanocomposites are promising materials for supercapacitor electrode. [Copyright &y& Elsevier]