Improving the Hydrophobicity and Insulation Properties of Epoxy Resins by the Self-Assembly-Induced Coating of Fluorinated Graphene.

Moisture and insulation deterioration are important factors that cause the failure of epoxy packaging materials. Thus, improving the long-term stability of epoxy resins in a hot and humid environment is an important prerequisite for electronic components to adapt to complex working conditions and achieve high power densities. In this study, fluorinated graphene doped with hydroxy-terminated poly(dimethylsiloxane) was prepared and self-assembled into a micro/nanostructure on the surface of an epoxy resin, which effectively improved the surface hydrophobicity of the epoxy resin. In addition, the doping with hydroxy-terminated poly(dimethylsiloxane) modified the fluorinated graphene filler, thereby forming an arch bridge energy band structure inside the epoxy resin and thus regulating carrier migration. The water absorption of the epoxy resin decreased from 1.02 to 0.24%, and the surface water contact angle increased from 93.58 to 133.2°. Moreover, the electrical insulation performance of the modified epoxy resin was greatly improved when the surface resistivity and flashover voltage increased by 50.5 and 36.4%, respectively. Therefore, the proposed method realizes a simultaneous improvement in the hydrophobicity and insulation of epoxy resins.

Effects of amine loading on the properties of cellulose nanofibrils aerogel and its CO2 capturing performance.

In this work, cellulose nanofibrils (CNFs) were used to develop novel amine-based aerogels that can be applied as adsorbents for CO2. Elemental analysis indicated that there was an increase in the C and N content when the concentration of aminosilane was higher. Moreover, Fourier transform infrared spectroscopy confirmed that the aminosilane had been grafted on the CNF. Thermal analysis and X-ray diffraction revealed that the thermal stability of the aerogel decreased after the modification, and the crystallinity decreased. However, the higher amine loading led to a rougher CNF surface and a larger average pore size, which favored the CO2 capture. Furthermore, CNF grafted with aminosilane displayed a high CO2 adsorption capacity (1.91 mmol/g 25 °C, 1 bar) and an easy regeneration process by heating at 80 °C. Therefore, the prepared polymer aerogels might have a highly potential use in the capture of CO2.

Synthesis of Porous Sulfonamide Polymers by Capturing Atmospheric Sulfur Dioxide.

The emission of SO2 from the burning of fossil fuel has resulted in a severe atmospheric pollution. The development of efficient strategies for not only capturing but also utilizing SO2 is highly welcome. A simple, mild, and versatile method has been developed that exploits atmospheric SO2 in the synthesis of porous polymers. Inspired by the chemistry of sulfonamides, contorted or bulky monomers with multiple amine groups were cross-linked by SO2 molecules in the presence of Et3 N and I2 . The sulfonamide polymers have specific surface areas up to 211 m2 g-1 . In contrast to most porous polymers, the porous sulfonamide polymers (PSPs) are soluble in organic solvents, thus offering a chance to study their structures and molecular weights by liquid-state NMR spectroscopy and gel-permeation chromatography, respectively. Moreover, these PSPs can be easily processed into organic membranes. The current concept should encourage more studies to design porous polymers with SO2 or CO2 gases as linkages.

Electrochemically Driven Transformation of Amorphous Carbons to Crystalline Graphite Nanoflakes: A Facile and Mild Graphitization Method.

Although, in the carbon family, graphite is the most thermodynamically stable allotrope, conversion of other carbon allotropes, even amorphous carbons, into graphite is extremely hard. We report a simple electrochemical route for the graphitization of amorphous carbons through cathodic polarization in molten CaCl2 at temperatures of about 1100 K, which generates porous graphite comprising petaloid nanoflakes. This nanostructured graphite allows fast and reversible intercalation/deintercalation of anions, promising a superior cathode material for batteries. In a Pyr14 TFSI ionic liquid, it exhibits a specific discharge capacity of 65 and 116 mAh g-1 at a rate of 1800 mA g-1 when charged to 5.0 and 5.25 V vs. Li/Li+ , respectively. The capacity remains fairly stable during cycling and decreases by only about 8 % when the charge/discharge rate is increased to 10000 mA g-1 during cycling between 2.25 and 5.0 V.

Synthesis and fungicidal activity of novel chloro-containing 1-aryl-3-oxypyrazoles with an oximino ester or oximino amide moiety.

Six novel chloro-containing 1-aryl-3-oxypyrazoles TMa-TMf with an oximino ester or an oximino amide moiety were prepared by the reaction of 1-aryl-1H-pyrazol-3-ols with benzyl bromide. Their structures were characterized by 1H-NMR, 13C-NMR, IR, MS, and elemental analysis. A preliminary in vitro bioassay indicated that compounds TMa, TMe and TMf displayed excellent fungicidal activity against Rhizoctonia solani and could be used as potential lead compounds for further development of novel fungicides.