Recently, the synthesis of organic materials with high porosity has received considerable scientific interest, and various chemical approaches have been applied to the build-up of microporous polymer networks. In a novel catalyst-free process using Schiff base chemistry, melamine has been reacted with various di- and trivalent aldehydes to form a series of highly cross-linked microporous aminal networks with BET surface areas as high as 1377 m(2)/g and a NLDFT micropore volume of up to 0.41 cm(3)/g. It was shown that through the proper choice of the starting compounds the porosity of the final material can be fine-tuned. The materials contain up to 40 wt % of nitrogen and were also found to exhibit high thermal stability. Owing to the cheap and abundant monomers used in this study these networks are promising candidates for large-scale applications in gas storage, gas separation, catalysis, and sensing.

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The proton conductivities of poly(vinylbenzyl phosphonic acid) (PVBPA) homopolymer and its statistical copolymers with 4‐vinyl pyridine [poly(VBPA‐stat‐4VP)s] are comprehensively studied in this work. Temperature and composition‐dependent “dry” proton conductivities of the copolymers have been determined and the self‐condensation of phosphonic acid groups has been quantified. The results show that the intrinsic proton conductivities of poly(VBPA‐stat‐4VP)s and PVBPA are quite low at 150 °C and exhibit time‐dependent changes due to anhydride formation at elevated temperatures. The effect of polymer composition on proton conduction shows a minimum at a 1:1 molar ratio of proton donor and acceptor groups and is discussed on the basis of the pKa values of the electrolyte species. A trace amount of water significantly increases conductivity probably due to additional hydronium ion diffusion and water bridging effects. Water content and proton conductivities of poly(VBPA‐stat‐4VP)s are determined at different relative humidities. High amounts of water are absorbed at high humidities leading to high proton conductivities.magnified image

Redispersible conductive core–shell nanoparticles with a polystyrene core and a polystyrene sulfonate shell loaded with polypyrrole (PPy) are constructed. The smooth conducting thin films assembled from the PPy core–shell nanoparticles show high transmittance in the visible range and adequate adhesion to the substrates. Performance of light‐emitting devices with the conducting thin film as the hole injection layer is tested and compared with the one based on PEDOT/PSS.