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Sol-gel based inorganic-organic hybrid coatings were developed and coated on aeronautical parts including cadmium plated steel and magnesium alloy. The hybrid coatings were targeted to provide two kinds of solutions. Firstly, the aim was to protect the cadmium-plating against the corrosion initiated especially by runway de-icing chemicals (formiate and acetate based). Secondly, the hybrid coating approach was targeted to provide alternative coating solutions for cadmium plating as well as hexavalent chromium conversion coatings. In order to improve the corrosion resistance of the selected substances, the chemistry of the inorganic backbone of the hybrid coating was varied by using silane and aluminium alkoxides. Furthermore, the organic components of the hybrid coating were also varied. The corrosion performance of the coated specimens were investigated by using standardised runway de-icing corrosion test (AMS G-12) and salt spray test (ISO 9227). Based on the AMS G-12 test results, the use of the hybrid coatings improved the corrosion protection of cadmium plating against runway de-icing corrosion. The salt spray test showed that the corrosion protection performance of the hybrid coating on cadmium-plating was similar to uncoated cadmium plating. In the case of magnesium alloy, the hybrid coating showed also better corrosion protection in the both corrosion tests compared to Cr6 conversion coating.

In our current study non-woven materials such as polypropylene (PP) and polyester (PES), used in filtration application, were modified in terms of surface properties by using hybrid coatings synthesised by using sol-gel method. The hybrid coatings consisted of organically modified silanes with fluorocarbon functionality in order to increase the hydrophobicity of the non-woven surfaces. Furthermore, superhydrophobic property was aimed to obtain by mixing silica (SiO2) nanoparticles into the coating matrix. Surface chemistry and topography of the coated specimens were characterised by using FTIR, AFM and SEM methods. The water contact angle measurements were used to detect the hydrophobicity. It was revealed that the hybrid coating with SiO2 nanoparticles increased the initial water contact angle from 117o up to 140o for PP and respectively from 87o up to 126o for PES non-woven.

New functional packaging coatings on paper, paperboard or plastic films are used for special and enhanced properties in the field of paper converting. The ever-increasing demands for the product properties, e.g. gas and grease barrier, combined with simultaneously increased line speeds make it challenging to achieve the desired level of performance required for these coatings. When using non-polar plastics such as polypropylene or polyethylene as base material, increasing of surface energy by pre-treatment with e.g. plasma or corona is necessary for adhesion. To answer these challenges, methods for atmospheric plasma pre-treatment and deposition of the functional hybrid coatings on polyolefin substrates have been developed in this work. The target of the developed coatings was to obtain barrier (e.g. oxygen and grease) and antimicrobial properties for polyethylene coated paper. The applying of the hybrid coatings was performed with atmospheric plasma assisted on-line spray coating method at a reel-to-reel extrusion coating pilot line.

In this study novel and functional added value e.g. easy-to-clean, wear resistance and anti-ice was performed for aluminium surfaces by hybrid coatings prepared by sol-gel method. In addition, the potentiality of the developed sol-gel coatings to be used as a novel sealing method for anodized aluminium was investigated. The sol-gel coatings were targeted to perform a durable hydro- and oleophobic properties for the aluminium substrates. Furthermore, the effect of sol-gel chemistry on the repellence properties was studied. In addition, different additives and concepts were used to develop anti-ice coatings. The properties and performances were characterised with contact angle measurements, cleanability tests, wear tests, anti-ice tests and profilometer analysis. It was observed that a durable easy-to-clean property for the aluminium product was achieved by the developed coating. Furthermore, compared to easy-to-clean behaviour of the non-sealed aluminium, we noticed that the developed hybrid sol-gel coating improved substantially the cleanability of the non-sealed aluminium surface. The anti-ice coatings showed promising ice-repellent behaviour by decreasing the ice adhesion strength.