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This paper aims to find the optimal deposition conditions for achieving the homogenous structure of the silver layers onto three types of polymeric substrates as well as on the rigid substrates. For this reason, the detailed investigation of the silver-based layers deposited at different technological conditions by microscopic methods is presented in this paper.

The special test pattern has been designed and deposited at different substrate temperatures by using two types of generally available silver-based nano-inks. Cross-sections and 3D profiles of the deposited silver layers have been profoundly analysed by using the optical profiler Sensofar S Neox on the generally used polymeric (PI, PET and PEN) and rigid substrates (951 and 9K7 LTCC, glass and alumina).

The results prove the strong correlation between the substrate temperature during the deposition process and the final shape of the created structure which has the a direct impact on the layers’ homogeneity. The results also prove the theory of the coffee ring effect creation in the inkjet printing technology.

The main benefit of this paper lies in the possibility of the homogeneity achievement of the deposited silver-based layers on the several polymeric and rigid substrates by managing the temperature during the deposition. The paper also offers the comparative study of nano-inks’ behaviour on several polymeric and rigid substrates.

This paper aims to find an optimal surface treatment of commonly used polymeric substrates for achieve the high adhesion of printed structures. For this reason, the investigation of substrates surfaces from different perspectives is presented in this paper.

The contact angle measurements as well as the roughness measurements were realised for the analysis of surface properties of investigated substrates. The impact of applied chemical agents for surface treatment onto the wettability is analysed for polyimide, polyethylene terephthalate and polyethylene naphthalene substrates.

The results prove the correlation among wettability, surface energy and work of adhesion with respect to the theoretical background. The surface treatment of polymeric substrates by chemical agents, such as acetone, toluene, ethanol, isopropyl and fluor silane polymer, has a significant impact onto the wettability of substrates which affects the final deposition process of nanoinks.

The main benefit of the surfaces’ investigation presented in this paper lays in surface modification by readily available chemical agents for optimising the deposition process nanoinks used in inkjet printing technology.

This paper reports on the development of a simple manufacturing process for polymeric multilayer substrates utilising the thermoplasticity of thermoplastic resin. Features and defects noted in manufacturing trials of the substrates are also reported. The process involves a polymer‐based thick film conductive paste screen printed on a hole‐punched thermoplastic resin film and dried. The films are stacked to form multiple layers and are then compressed into one unit. As the extremely thin thermoplastic resin film layers are equivalent to a single layer, a feature of this substrate is its exceptional thinness. As thermoplastic resin is used as a base material, the soldering process and other connecting technologies which may be used in place of solder connection are also examined.

304 SS substrates have been covered with polymeric class low melting barriers, like polyurethane, acrylate and epoxy with and without incorporation of eco‐friendly (non‐toxic) ceramic particular of antifouling origin. The results of corrosion resistance tests are encouraging. Other physical parameters like hardness, adhesion, scratch resistance are also studied, for these synergistically organized low melting point barrier layers.

The purpose of this paper is to evaluate and exploit the combination of additive manufacturing polymeric technology and structural adhesives. The main advantage is to expand the maximum dimension of the 3D printed parts, which is typically limited, by joining the parts with structural adhesive, without losing strength and stiffness and keeping the major asset of polymeric 3 D printing: freedom of shape of the system and low cost of parts.

The materials used in the paper are the following. The adhesive considered is a commercial inexpensive acrylic, quite similar to superglue, applicable with almost no surface preparation and fast curing, as time constraint is one of the key problems that affects industrial adhesive applications. The 3D printed parts were in acrylonitrile butadiene styrene (ABS), obtained with a Fortus 250mc FDM machine, from Stratasys. The work first compares flat overlap joint with joints designed to permit mechanical interlocking of the adherends and then to a monolithic component with the same geometry. Single lap, joggle lap and double lap joints are the configurations experimentally characterized following a design of experiment approach.

The results show a failure in the substrate, due to the low strength of the polymeric adherends for the first batch of typical bonded configurations, single lap, joggle lap and double lap. The central bonded area, with an increased global thickness, never does fail, and the adhesive is able to transfer the load both with and without mechanical interlocking. An additional set of scarf joints was also tested to promote adhesive failure as well as to retrieve the adhesive strength in this application. The results shows that bonding of polymeric AM parts is able to express its full potential compared with a monolithic solution even though the joint fails prematurely in the adherend due to the bending stresses and the notches present in the lap joints.

Because of the 3D printed polymeric material adopted, the results may be generalized only when the elastic properties of the adherends and of the adhesive are similar, so it is not possible to extend the findings of the work to metallic additive manufactured components.

The paper shows that the adhesives are feasible way to expand the potentiality of 3 D printed equipment to obtain larger parts with equivalent mechanical properties. The paper also shows that the scarf joint, which fails in the adhesive first, can be used to extract information about the adhesive strength, useful for the designers which have to combine adhesive and additive manufactured polymeric parts.

To the best of the researchers’ knowledge, there are scarce quantitative information in technical literature about the performance of additive manufactured parts in combination with structural adhesives and this work provides an insight on this interesting subject. This manuscript provides a feasible way of using rapid prototyping techniques in combination with adhesive bonding to fully exploit the additive manufacturing capability and to create large and cost-effective 3 D printed parts.

The purpose of this study is to investigate the authors' previously prepared and fully characterized poly (methacrylamide)-chitosan nanoparticles (CNPs) graft copolymer having 50.2% graft yield with respect to flocculation efficiency for ferric laurate aqueous dispersions. This was done to compare the ability of the latter cheap, biodegradable and ecofriendly hybrid natural-synthetic polymeric substrate as a flocculant in comparison with higher cost, nonbiodegradable and harmful polyacrylamide as a well-known synthetic flocculant counterpart.

The graft copolymerization process was carried out at 450°Cfor 120 min using (1.0 g) CNPs, methacrylamide (1.5 g), 100 mmol/l potassium chromate and 80 mmol/l mandelic acid. Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis and specific viscosity were used to characterize and analyze the resultant copolymer. The flocculation efficiency was conferred in terms of transmittance % and weight removal %. The main factors influencing the flocculation process, such as flocculent dose, flocculation medium pH, stirring speed, flocculation temperature and grafting extent, were comprehensively discussed.

The flocculation efficiency of the prepared copolymers revealed the following findings: increased by increasing the flocculant dose, pH, temperature and stirring speed to a maximum values denoted at 30 ppm, 6.0, 30°C and 50 r/min, respectively, then decreased thereafter; increased by increasing the extent of grafting within the range studied; showed a comparable flocculation efficiency in comparison with polyacrylamide as a synthetic polymeric flocculent; and, finally, a preliminary bridging mechanism representing the attraction between the anionic suspended particles ferric laurate and cationic poly (MAam)-CNPs graft copolymer has been projected.

The advancement addressed here is undertaken with using the authors’ poly (MAam)-CNPs graft copolymers having different extent of grafting (a point which is not cited in the literature especially for the authors’ prepared copolymer) as a hybrid natural-synthetic polymeric substrate as a flocculant for ferric laurate aqueous dispersions in comparison with the high cost and nondegradable polyacrylamide synthetic flocculant.

Discusses the particulation of organic barrier layers, based on laboratory‐bench data, obtained from the exposure of painted panels in low, high or neutral pHelectrolytes. It also discusses their compatibility with the succeeding and preceding layers and the galvanic interactions at the layer substrate interfaces. Aspects like substrate effect, leaching of the micaceous iron powder, role of high temperature and hydrodynamic disturbances and distribution of ultrafine particulates have been highlighted using potential versus time plot, AAS data, and galvanic current measurements and XRD analysis. Exposure tests conducted under ambient conditions and under very strong hydrodynamic disturbances, revealed superior properties of the SiC particulated epoxy based barrier layers.

This paper will review rework of multi‐chip modules (MCMs). The issues of die removal from substrates (i.e., PCBs) with different chip‐to‐substrate interconnect technologies will be explored in detail. These different interconnect technologies (e.g., wire bonding, tape automated bonding and flip chip bonding) and die‐attachment methods (e.g., eutectic and adhesive) have a strong influence on the MCM rework process and equipment selection. Traditional surface mount (SM) and current MCM rework technologies are also compared. It will be shown that traditional SMT rework processes and equipment are unable to solve the level of difficulty involved in fine‐pitch MCM device removal—especially for systems which require heat removal through the substrate.

Metal cans are extensively used, in the retail distribution of foods and beverages, where packaging is required to be both robust and able to withstand sterilisation temperatures. Internal lacquer barrier coatings on the cans play an important role in maintaining the quality of the contents, by preventing any unacceptable metal contamination. It is, however, necessary to ensure that the presence of the lacquer does not itself make the contents unsafe. As yet, the European Commission has produced no directive relating specifically to safety rules for contact between foodstuffs and polymeric or plastic coatings on metal substrates (e.g. lacquer‐coated cans). It is therefore necessary to turn to individual national laws and regulations, or the Council of Europe Resolution on Coatings, for assurance on the safety of lacquer‐coated food and beverage cans. Discusses existing EC food contact legislation, and its possible future application to lacquer‐coated food and beverage cans.

Metal cans are extensively used, in the retail distribution of foods and beverages, where packaging is required to be both robust and able to withstand sterilisation temperatures. Internal lacquer barrier coatings on the cans play an important role in maintaining the quality of the contents, by preventing any unacceptable metal contamination. It is, however, necessary to ensure that the presence of the lacquer does not itself make the contents unsafe. As yet, the European Commission has produced no directive relating specifically to safety rules for contact between foodstuffs and polymeric or plastic coatings on metal substrates (e.g. lacquer coated cans). It is therefore necessary to turn to individual national laws and regulations, or the Council of Europe Resolution on Coatings, for assurance on the safety of lacquer coated food and beverage cans. Discusses existing EC food contact legislation, and its possible future application to lacquer coated food and beverage cans.