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Dynamic Interactive Systems are defined by networks of continuously exchanging and reversibly reorganizing connected objects (supermolecules, polymers, biomolecules, pores, nanoplatforms, surfaces, liposomes, cells). They are operating under the natural selection to allow spatial / temporal and structural / functional adaptability in response to internal constitutionalor to stimulant external factors. In this minireview we will disscuss some selected examples of organic/inorganic SYSTEMS MATERIALS, covering a) the sol-gel resolution of constitutional architectures from Dynamic combinatorial libraries and b) the generation of Dynamic Hybrid Materials and SYSTEMS MEMBRANES able to evolve insidepore architectures via ionic stimuli so as to improve membrane transport functions.

With the growing search for sustainable and economically viable materials, polyphenol-based plant extractives called tannins have been gaining space in the packaging market. In this work, tannin from black wattle (Acacia mearnsii De Wild) was used as an antioxidant additive in a polystyrene (PS). PS films were prepared with 1, 3, and 5% by weight tannin. The films were exposed for 3 weeks to accelerated aging process. The Fourier transform infrared spectroscopy (FTIR) and ultraviolet–visible spectroscopy (UV–Vis) were used to monitor the photodegradation. The samples were also evaluated by contact angle, scanning electron microscopy (SEM), and mechanical thermodynamic analysis (DMA). It was possible to verify the progressive reduction of the photodegradation process of the samples when subjected to the increasing addition of tannin over the weeks of exposure to UV-C light. The results showed that the film with 5% tannin additive presented the highest antioxidant protection among all analyzed compositions.

Electrical switching due to metallic filament formation in hydrogenated amorphous silicon (a-Si:H) is studied in metal/a-Si:H/metal structures. We examine the effects of a-Si:H switch layer thickness, applied voltage and polarity, metal contact material, and contact interface properties. For switching, the voltage applied to the contacts must be large enough to establish: 1) a minimum threshold voltage of about 2V at the contacts and 2) a bias field of about 1 MV/cm in the bulk. Changing contact material and polarity strongly affects the switching behavior.