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The aim of this investigation was to determine the role of negative direct current and alternating current (plasma) corona treatments in modification of bio-based dispersion barrier coatings and the response of replacing fossil-based binder with a thermoplastic bio-based binder (starch). The study emphasizes the importance of understanding and optimizing electric corona discharge in order to obtain high oxidation level without harming the substrate and causing unintentional treatment of the reverse side. The coatings were exposed to different corona treatment conditions using a novel developed sheet-fed laboratory-scale device. Corona-induced topographical, mechanical and surface chemical changes were observed from atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and contact angle and surface energy measurements. XPS results indicated further that partial starch decomposition occurred after plasma treatment. Coated surfaces became substantially smoother after both treatments suggesting that nanoparticle migration and re-orientation effects occurred. Additionally, reverse side effects and strike through were also discussed., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Star-shaped charge-transporting materials with a triphenylamine (TPA) core and various phenylethenyl side arm(s) were obtained in a one-step synthetic procedure from commercially available and relatively inexpensive starting materials. Crystallinity, glass-transition temperature, size of the π-conjugated system, energy levels, and the way molecules pack in the solid state can be significantly influenced by variation of the structure of these side arm(s). An increase in the number of phenylethenyl side arms was found to hinder intramolecular motions of the TPA core, and thereby provide significant enhancement of the fluorescence quantum yield of the TPA derivatives in solution. On the other hand, a larger number of side arms facilitated exciton migration through the dense side-arm network formed in the solid state and, thus, considerably reduces fluorescence efficiency by migration-assisted nonradiative relaxation. This dense network enables charges to move more rapidly through the hole-transport material layer, which results in very good charge drift mobility (μ up to 0.017 cm(2) V (-1) s(-1))., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)