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Over the past few decades, radio frequency identification (RFID) technology has been an important factor in securing products along the agri-food supply chain. However, there still exist security vulnerabilities when registering products to a specific RFID tag, particularly regarding the ease at which tags can be cloned. In this paper, a potential attack, labeled the "Hilt Shao attack", is identified which could occur during the initial phases of product registration, and demonstrate the type of attack using UID and CUID tags. Furthermore, a system is proposed using blockchain technology in order for the attacker to hide the cloned tag information. Results show that this attack, if carried out, can negate the profits of distributors along the supply chain, and negatively affect the consumer.

Novel hyperbranched alkyd resins (HBAs) were synthesized by reacting the hydroxyl end-groups of the prepared hyperbranched polyesters, based on 1,3,5-tris(2-hydroxyethyl) cyanuric acid (THECA) as a trifunctional core, with different oil fatty acids, namely, linseed, soya and sunflower oil fatty acids. Resins of different compositions of HBAs were prepared by changing either the fatty acid or the generation of the hyperbranched polyester. Their molecular structures were identified using IR and 1 H and 13 C NMR spectroscopy. The thermal stability, glass transition temperatures and rheological properties were investigated. All of the alkyd resins exhibited initial decomposition temperature at values >300 °C. The decreased Tg values of LG3, SG3 and SFG3 render them suitable for use as coatings that are applied at ambient temperature. All HBAs show Newtonian behaviour and the viscosity was ranging between 1.2 and 5.2 Pa s. Film properties of the prepared alkyd resins using different driers were determined and it has been found that all samples exhibited good adhesion, bending, impact, ductility, and high gloss, but show low hardness.

An approach to modify the properties of UV curable polyurethane coatings by altering the amount and functionality of acrylic reactive diluents, in order to optimize the coating performance, is demonstrated. Based on the rheology analysis, a model of the rheological behavior of the UV curable materials depending on the amount and type of a reactive diluent in the composition is demonstrated in this study. The relationships between the rheological behavior, the mechanical properties and adhesion of the coatings prepared from polyurethane UV curable compositions containing different amounts and functionalities of acrylic reactive diluents, have been investigated and discussed in this study. Based on the results of the study, the desired properties of UV cured coatings can be modeled and controlled without changing the nature of a particularly selected oligomer, thus maintaining the advantages of its chemical structure in a coating composition.

Barrier properties of packaging materials against moisture and oxygen penetration are of high relevance. Enhanced protection of existing materials against weather conditions can be achieved by application of printed coatings. To improve barrier performance of packaging materials, new inks for obtaining printed coatings with a layered structure were developed and investigated. The proposed ink compositions for flexographic printing on paper substrates are based on an environmentally friendly acrylic binder and contain inorganic fillers with platelet particles incorporated in the polymer matrix. Coatings based on the developed printing inks demonstrate significantly decreased water vapour permeability compared to traditional polymer inks. The effect of decreased permeability was investigated considering inks rheological behaviour, the coating structure, mechanical properties, surface energy and water uptake for different ink formulations. The developed inks provide variable optical properties including coatings with a relatively high transparency. The development of the functional barrier inks contributes to saving natural resources by prolonging life performance of packaging materials and goods.

In the European project MANIAC-Innovative Measurement Methodology in Quality Assessment of Coating, a methodology was developed to assess the long term durability of coatings. The project was focused on environmentally friendly waterborne automotive multi-layer coating systems. Although developed for waterborne coatings, the methodology is very generic and can be applied to all kinds of coatings. The first step in the evaluation of long-term performance of automotive coatings involves exposures to weathering (natural as well as artificial). Traditionally, the durability of coatings is evaluated by examining the changes in performance properties like gloss, color, and scratch resistance. In the MANIAC methodology, the focus is on changes in structures on molecular levels. Microtomed slices of the coatings were examined by FTIR spectroscopy for monitoring oxidation. UV spectroscopy and GC-MS were used to study the migration of additives like HALS and UVA. In the methodology, the environmental variables (outdoors as well as indoors), e.g., temperature, relative humidity, UV irradiation, were carefully monitored and included in the modeling scheme. The results from accelerated tests are modeled and, together with outdoor climatic data, the different models are used to predict degradation during outdoor exposure.