Due to the wide-ranging of preservative surfaces applications, there is a need for a fundamental understanding of not only how to produce such exceptional surfaces but also to know how specific surface properties affect coatings pore wettability, for example, morphology and chemical comprehending. Silica-based hybrid coatings as advanced hybrid polymers have been shown to exhibit excellent chemical stability with a chance to functionalize combined with reducing the corrosion of metal substrates. However, researches show that sol-gel only has some limitations in terms of the period of anti-corrosive properties due to the high porosity. Therefore, this work will report the preliminary performance of the diffusion prevention in a silica-based hybrid sol-gel coating that has been enhanced by adding Oleic acid (OA) to the sol-gel formula. The evaluation of the effect of the adsorption mechanism of OA on aluminium alloys surface was studied based upon using infrared analysis (FTIR) as a non-destructive test separately. The chemical confirmation of adding OA to Sol-gel was done by infrared spectroscopy (ATR-FTIR) and supported by analyzing the morphology of the surface by using scanning electron microscopy (SEM) and water contact angle test (WCA). Furthermore, the coatings' corrosion performances were studied using electrochemical impedance spectroscopy (EIS) and Potential-dynamic polarization scanning (PDPS). As a result, the Oleic acid - silica-based hybrid coating exhibited exceptional functionalized pore-blocking, hydrophobic and anti-corrosion properties, providing mimicked active protection on the aluminium alloy 2024-T3 samples compared to sol-gel-only and non-coated samples.

With the transition towards more sustainable paints formulations based on waterborne environment, their susceptibility for microbial contamination has to be better controlled in order to increase shelf life and functional lifetime. However, recent restrictions in European regulation on use of biocides have put limitations on the possibilities for traditional systems providing either in-can or dry-film preservation. The commercial technologies for in-can preservation that are currently available are based on 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT) or 2-methyl-4-isothiazolin-3-one (MIT). At present, only limited number of alternatives can be used and are reviewed in this presentation. The examples of non-sensitizing biocidal components for coatings may include quaternary/cationic nitrogen amines, silver ion or zinc complexes. However, the use of the latter is not without risk for human health. Therefore, it is believed that disruptive methods will need to be implemented in parallel with bio-inspired solutions. In particular, the antimicrobial polymers, amino-acid based systems and peptides have similar functions in nature and can offer potential for antimicrobial activities. Also cross-border solutions currently applied in food or cosmetics industries need to be considered as examples that need be adapted for paint formulations. However, the incorporation in paint formulations remains challenging in respect of the stabilization and rheology control of the system. The overview in this work aims to provide different strategies and best evidence for future trends.

Zinc oxide is an active, inorganic material for a number of important applications. Zinc Oxide have wide properties for industrial applications which has been further increased by making the use of it in nanoscale size that fit in the corrosion resistant coatings. Nanoparticles have unique properties such as large surface area and nanoscale size due to which it possess various application in coatings and paints. Coating is a covering which when applied to the surface forms a layer and act as a protective barrier to the surface based on the property of the coating. Nanocomposite coatings are comparatively low cost and have more applications like dealing with the corrosion and radiation resistivity. Incorporation of nanoparticles in coating enhance its property by reducing the void and expected to induce barrier property for corrosion.

For this purpose, zinc oxide nanoparticles were synthesized using wet chemical method. The effect of reactants (base) used in ZnO synthesis was studied from pH 9 to 11 and was characterized using XRD, FT-IR, SEM-EDX, etc. To increase the hydrophobicity and to make them suitable to disperse in polymeric binder, synthesized ZnO nanoparticles, have been surface modified with different silanes such as aminopropyl triethoxy silane (APTES), hexadecyl trimethoxy silane (HDTMS) and vinyltriethoxy silane (VTES). Surface modification was examined by FTIR, TGA, SEM-EDX and Contact angle analysis and VTES was found suitable for surface modification. Surface modified ZnO nanoparticles have been dispersed in polymeric binder (liquid EPDM) with other additives to form coating formulations. These coating formulations were applied on MS panels and it was observed that developed coating formulations have good mechanical and physical properties and high corrosion resistance.

Poly(butylene succinate) (PBS) is a bio-based and biodegradable polyester, that can be used in numerous applications ranging from clothing to food packaging and from car industry to biomedical sector (e.g. drug release systems). PBS conventional polymerization method requires the presence of metal-based transesterification catalysts (e.g. titanium-based catalysts) and high reaction temperatures (T>150 °C). However, under these conditions side reactions may occur along with undesirable yellowing.

Green polymerization routes such as biocatalysis are being developed. However, there is a very limited literature on the enzymatic synthesis of PBS. Additionally, in most of the works where high-molecular-weight PBS is produced from the typical monomers (BDO and DES), several drawbacks e.g. the use of various solvents for polymer isolation, the requirement of high vacuum for by-products removal may impede the process scaling up.

On that basis, an eco-friendly, solvent-free, enzyme-based process for the production of PBS was applied. It was conducted in two steps with the use of Novozym 435: the first at 40°C, under atmospheric pressure for 24 h and the second at 90°C, 20 mbar for 2 h. This work focused on the optimization of the second step’s conditions, by varying reaction temperature (80°C-95°C), pressure (20 mbar, 200 mbar) and reaction time (2h, 6h). Based on the optimization results, the process was scaled up (ca. 10 g of product). A free of thermal degradation and metal catalyst residues PBS grade of weight-average molecular weight 4700 g/mol and melting point 103°C was obtained.

Self-assembled nanoparticles based on amphiphilic poly(N-vinylpyrrolidone) (Amph-PVP) were earlier proposed as a new drug delivery system. In current work, we studied antitumor activity of Amph-PVP-based self-assembled polymeric micelles covalently conjugated with the antitumor receptor-specific TRAIL variant DR5-B (P-DR5-B). The Amph-PVP polymer was synthesized by the earlier developed one-step technique (Kulikov et al., Polym. Sci. Ser. D, 2017). To stabilize Amph-PVP associates, the hydrophobic core was loaded with model substance prothionamide. For covalent conjugation with DR5-B, hydrophilic ends of polymeric chains were modified with maleimide, and a DR5-B N-terminal amino acid residue valine was mutated to cysteine (DR5-B/V114C). DR5-B/V114C was conjugated to the surface of polymeric micelles by the selective covalent interaction of N-terminal cysteine residue with maleimide on Amph-PVP.

The cytotoxicity of DR5-B-conjugated Amph-PVP polymeric nanoparticles was investigated in 3D multicellular tumor spheroids (MCTS) of human colon carcinoma HCT116 and HT29 cells, generated by the RGD-induced self-assembly technique (Akasov et al., Int. J. Pharm., 2016). In DR5-B-sensitive HCT116 MCTS, the P-DR5-B activity slightly increased compared to that of DR5-B. However in DR5-B-resistant HT29 MCTS, P-DR5-B significantly surpassed DR5-B in the antitumor activity. Thus, conjugation of DR5-B to the Amph-PVP nanoparticles enhanced its tumor cell killing capacity.

In current study we obtained a new nano-scaled delivery system based on Amph-PVP self-aggregates coated with covalently conjugated antitumor DR5-specific cytokine DR5-B. P-DR5-B overcomes DR5-B-resistance of the human colon carcinoma MCTS in vitro. This makes Amph-PVP polymeric nanoparticles a perspective versatile nano-scaled delivery system for the targeted proteins.