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The corrosion of metal surfaces is one of the most critical issues in aviation, where aircraft are subjected to very extreme climatic and operating conditions. Hexavalent chromium, Cr (VI), based coatings provide an effective corrosion protection at relatively low cost, but unfortunately their usage has a significant impact on the environment. To comply with new regulations (REACH) and to ensure effectiveness against corrosion, the current interest of researchers and investors is focused on the synthesis and the design of eco‐friendly and safer coatings, to develop an alternative and innovative corrosion protection coating systems, characterized by specific performance in terms of good adhesion, barrier, and rheological properties. The development of innovative materials and the implementation of new technologies can allow widening the safety window in all the process phases from the production to the disposal. These research activities are focused on the development of anticorrosive and chromate‐free coatings, by modifying metal‐based primer formulations. The aim is toward the improvement in the anticorrosive performance and durability respect to the systems already known in the literature through the incorporation of sustainable compounds or less toxic metals as corrosion inhibitors to reduce the environmental impact. [ABSTRACT FROM AUTHOR]

Fibrillary cellulose and nanocellulose are widely applied as fillers for the improvement of the mechanical properties, thermostability, and biodegradability of polymers. Here, an opposite concept is suggested which is to use cellulose for structure‐forming and directing the scaffold, whereas polymers serve for its modification. Cellulose possesses excellent properties, but they are badly affected by water; its mechanical strength drops sharply, cellulosic materials swell, become dimensionally unstable, and susceptible to fungal degradation. The deterioration of properties gives no way of using methods of wet chemistry for cellulose treatment. To obviate this problem, dimensionally stable aerogels are prepared from microfibrillated cellulose. Their stability allows them to be treated in solutions of isocyanate. Polyurethane synthesized in situ is attached covalently to cellulose through hydroxyl groups. Polymer coating further stabilizes the 3D microfibrillar network, Young's modulus increases by more than two orders of magnitude and differences in the properties of aerogels in the dried and wetted states are minimized. Improvement of the mechanical strength makes cellulose aerogels better suitable for various applications than present cellulosic materials. Cellulose serves as a main structure‐forming scaffold for coating by polyurethane synthesized in situ. To perform treatment in solutions, dimensionally stable aerogels from microfibrillated cellulose are prepared. Diisocyanate interacts with hydroxyl groups with the formation of polymer on polysaccharide macromolecules that increases mechanical strength by two orders of magnitude, and minimizes the difference in properties of aerogels in dried and wetted states. [ABSTRACT FROM AUTHOR]