In this work, the electrospinning technique is used for the synthesis of micro/nanofibers using a polymeric precursor with hydrophobic (even superhydrophobic) behaviour such as polystyrene (PS) or polyvinyl chloride (PVC). These electrospun fibers are deposited onto aluminum substrates (6061T6). The effect of varying the different electrospinning deposition parameters (mostly applied voltage and flow-rate) will be exhaustively analyzed in order to optimize the resultant electrospun coatings. Several fiber characterization tests have been performed, including Field Emission Scanning Electron Microscopy (FE-SEM), Atomic Force Microscopy (AFM), Termogravimetric analysis (TGA), Optical Microscopy (OM) and Water Contact Angle (WCA) measurements. Furthermore, the anti-corrosion properties of these electrospun coatings can be enhanced by the addition of metal oxide nanoparticles (ZnO) which act as corrosion inhibitors. Finally, electrochemical corrosion tests (Tafel and pitting tests) have been perfomed, showing an improvement in the resultant corrosion resistance of the aluminum alloys coated by the combination of both polymeric film with metal oxide inorganic nanoparticles.

Milk whey (MW) represents the major by-product of cheese industry. One possibility to recycle the MW wastes is the use of their globular proteins (MWPs) as a polymer source for the production of biodegradable plastic materials. MWP-based films are usually obtained by protein heat treatment in the presence of glycerol (GLY) as plasticizer at pH 7, a method which would require commercially high costing process. In this work it was exploited the possibility to produce manageable MW-derived biomaterials without any heat-treatment but under alkaline conditions. Our results demonstrated that the casting at pH 12 of the unheated MWP film forming solutions (FFSs), containing either 40% or 50% GLY, led to produce more resistant and flexible biomaterials than the ones obtained at pH 7. Also film transparency was observed significantly improved, being lower in the samples obtained at alkaline pH without MWP heating and with higher GLY concentrations. Finally, moisture content decreased with the reduction of GLY content, both in heated and unheated MWP-based films, whereas water uptake of the different films prepared at pH 12 did not significantly change.

Magnetron sputtering is a useful tool for producing coatings on various substrates at low temperature. The use of an austenitic stainless steel target in a nitrogen-containing plasma mixture allows to obtain nanostructured coatings with the formation of the so-called S phase, supersaturated interstitial solid solution of nitrogen in the expanded and distorted austenite lattice, which shows improved hardness and higher corrosion resistance in comparison with the bulk alloy. In the present research, RF magnetron sputtering deposition of austenitic stainless steel coatings using an AISI 316L target in nitrogen-containing plasma gas was studied. The effect of the N₂/Ar gas ratio and the deposition temperature on nitrogen content, phase composition and crystallite size is investigated by mean of XPS, XRD and electron microscopy analyses. The results show that the nitrogen content in the resulting deposit slightly depends on the N₂/Ar ratio in the chamber during the deposition, reaching a maximum value of about 35% with a 30% N₂/Ar gas composition mixture in the chamber. Data obtained on different substrates are presented and a preliminary evaluation of the corrosion resistance behaviour is also reported.

Corrosion testing is a very important step in quality control for metal industrial processes. Especially for electroplated goods, corrosion resistance is a primary indicator of surface quality. International Standard Organization has established several standards that use Electrochemical Impedance Spectroscopy (EIS), alone or combined with other electrochemical techniques, to determine corrosion resistance of metal surfaces such ISO 16773 for testing coated and uncoated metallic specimens and ISO 17463 specially designed for organic-coated metal surfaces. EIS is a versatile procedure for the accelerated evaluation of the anti-corrosion performance of coatings: unlike other standard procedures is generally a non-destructive method. EIS works applying an electrical sinusoidal perturbation with a fixed frequency and measuring electrical impedance Z of the sample. Measuring impedance at different frequencies and analysing the data it is possible to postulate the structure of an equivalent circuit and extract corrosion resistance data. This approach is commonly used for high-impedance coatings, in this study we will explore EIS as well as the OCP measurement, the corrosion current and other techniques to find the best option for low-impedance metallic coatings analysis. The objective of this study is to develop a method to determine corrosion resistance for electroplated goods that can give results as reliable as other more diffuse and traditional destructive corrosion testing techniques (such as corrosion tests in artificial atmosphere ISO 9227 and ISO 17228) with a non-destructive process and in a fair less amount of time.

The most disadvantage of the fried falafel balls are the highest level of acrylamide formed during Maillard reaction. Falafel balls are one of the largest deep fat frying fast food in the Middle East made basically of chickpeas. The main aim of this study was to investigate the effect of adding transglutaminase (TG, E.C. 2.3.2.13) to the falafel dough followed or not by dipping into pectin (PEC 1%) coating solution. Acrylamide, oil and water content of the fried falafel balls treated or not by TG (5 or 20U/g of chickpea proteins) and coated or not with PEC-containing film forming solutions were evaluated. In addition, the texture profile analyses were carried out. We observed, by TOF LC/MS, that the acrylamide content was reduced, compared to control sample, by 10.8% and 34.4% in the samples set up by adding 5 and 20 U TG/g respectively. In PEC-coated samples, acrylamide reduction was about by 59%, 65.3% and 84.5%, in falafel balls prepared either without of TG or containing 5U or 20 U of the enzyme, respectively, suggesting that TG-mediated crosslinks increase the water content inside the falafel balls, thus, reducing the rate of Maillard reaction. However, TG treatment does not affect oil content, while the PEC coating reduces the oil uptake about 23.5%. Finally, no difference was observed between the control sample and the one dipped in PEC regarding their texture properties hardness, chewiness and gumminess, while these properties were influenced in samples set up in the presence of the enzyme.