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The inhibiting effects of 2,6‐ionen and 2,10‐ionen type polyvinylbenzyltrimethylammonium chloride, and latex, on low carbon steel in hydrochloric acid solution was investigated by potentiodynamic polarisation measurements and impedance measurement techniques over the temperature range of 20‐60°C at different inhibitor concentrations. It was found that the inhibition efficiencies increased with increasing inhibitor concentration. The degree of shift in E_corr values, together with the change in anodic and cathodic Tafel slopes (β_a, β_c), revealed that the studied inhibitors behaved as anodic inhibitors. Thermodynamic and kinetic parameters for dissolution and adsorption were also calculated.

This study aims to fabricate a cool phthalocyanine green/TiO₂ composite pigment (PGT) with high near-infrared (NIR) reflectance, good color performance and good heat-shielding performance under sunlight and infrared irradiation.

With the help of anionic and cationic polyelectrolytes, the PGT composite pigment was prepared using a layer-by-layer assembly method under wet ball milling. Based on the light reflectance properties and color performance tested by ultraviolet-visible-NIR spectrophotometer and colorimeter, the preparation conditions were optimized and the properties of PGT pigment with different assembly layers (PGT-1, PGT-3, PGT-5 and PGT-7) were compared. In addition, their heat-shielding performance was evaluated and compared by temperature rise value for their coating under sunlight and infrared irradiation.

The PGT pigment had a core/shell structure, and the PG thickness increased with the self-assembly layers, which made the PGT-3 and PGT-7 pigment show higher color purity and saturation than PGT-1 pigment. In addition, the PGT-3 and PGT-7 pigment showed 11%–16% lower light reflectance in the visible region. However, their light reflectance in the NIR region was similar. Under infrared irradiation the PGT-5 and PGT-7 pigment coating showed 1.1°C–3.4°C and 1.3°C–4.7°C lower temperature rise value than PGT-1 pigment coating and physical mixture pigment coating, respectively. And under sunlight the PGT-3 pigment coating showed 1.5–2.6°C lower temperature rise value than the physical mixture pigment coating.

The layer-by-layer assembling makes the core/shell PGT composite pigment possess low visible light reflectance, high NIR reflectance and good heat-shielding performance.

The rheological properties of coating suspensions containing a blend of clay and CaCO3 as a pigment have been evaluated at 22°C, using a rheometer with shear rates from 0.5 to 100rpm. The state of dispersion of the pigment, the structure viscosity of the suspension as a result of pigment‐pigment or pigment‐binder interactions, and its behaviour by changing the solid content and ionic strength, were limited from the examination of the flow curves. The flow parameters for each suspension were calculated. The results showed that changes in solid content and ionic strength by the addition of divalent simple electrolyte (CaCl2) and pH level have a more profound effect on the flow parameters than that obtained by the addition of monovalent simple electrolyte (NaCl) or polyelectrolyte soluble polymers (CMC) with different degrees of substitution. The type of acid used to adjust the pH of the suspension also has a great influence on the flow parameters.

The purpose of this paper was to study the corrosion resistance of AA2024 alloy using surfactant-modified halloysite nanocapsules capable of holding benzotriazole (BTA) as the corrosion inhibitor and discharging it into the solution.

The effect of surfactant shells was studied by surfactant-modified halloysite nanotubes fabricated through assembly of two types of cationic surfactants. The zeta potential and size distribution measurements were performed using a Zetasizer Nano. The concentration of BTA during release into the solution was detected by using a UV–vis spectrophotometer. The anti-corrosion activity of nanocapsules as free agents with respect to the AA2024 alloy was investigated using the potentiodynamic scan (PDS) method. An epoxy resin doped with nanocapsules was used as an anti-corrosion coating deposited on the AA2024 alloy. The corrosion protection performance of coatings was studied by using the electrochemical impedance spectroscopy (EIS) method.

The results indicate that the release of the inhibitor from nanocapsules depends on the surfactant shell components. The PDS results confirmed the feasibility of developing “smart” corrosion protection by inhibitor-loaded nanocapsules. The results of EIS measurements showed that the coating with the nanocapsules exhibited enhanced corrosion protection in comparison with the undoped coating.

The findings of this paper indicate that surfactant-modified halloysite nanocapsules can be added to epoxy resin coatings to improve their corrosion protective properties for the AA2024 alloy.

The word polyelectrolytes bobbed up ubiquitously at Earls Court during the Convention sessions held from March 30 to April 2. The thread‐like nature of the ionised molecules of these materials, and their other principal advantage of water‐solubility, are finding more and more uses in clarifying, sedimenting, thickening, sludge filtration and dewatering operations. Polyacrylamides of MW 105–5 X 106 are among the more recent types used for controlling mud and silt in cooling systems, the dosage being 0.05–200 p.p.m.

The purpose of this paper is to present a novel manufacturing process that aims to pattern metal tracks onto polyimide at atmospheric pressure and ambient environment. The process can be scaled up for industrial applications.

From a thorough literature survey, different approaches were carried out for processing polyimide. Following a design of experiments for the processing and various characterisation techniques, a micro‐coil was manufactured as a test demonstrator.

The characteristics of some main formaldehyde‐based electroless copper baths were compared. The quality of the sidewalls was characterised and the performance of the process was assessed.

This paper demonstrates a high‐value manufacturing technique that is mass manufacturable, low cost and suitable for use on 3D surfaces. Criteria required for the development of a direct‐writing process have been described. The issues surrounding electroless plating on polyimide have been explained.

SMA 1440H, a member of ARCO Chemical Co's family of low molecular weight styrene and maleic anhydride copolymers has established a new level of performance in pigment dispersion technology. Coatings manufacturers have developed commercial formulations in which SMA 1440H has been shown to perform as an all inclusive one component dispersant in latex paint formulations; replacing as many as 4–5 other types of dispersants. Because of its anionically charged chemical structure and complementary design of hydrophilic‐hydrophobic properties, SMA 1440H can effectively disperse and stabilise many different types of pigments. SMA 1440H, a polyelectrolyte resin becomes water insoluble as the paint film cures and, therefore, contributes to film reinforcement. SMA 1440H is the ammoniacal solution of SMA 1440A.

The purpose of this paper is to prepare a dual-encapsulated halloysite nano-container to release the capsuled inhibitor as an additive for corrosion protection of epoxy coating.

Halloysite nano-containers (HNT) were prepared by simultaneously implanting inhibitor benzotriazole (BTA) into the inside and outside of the halloysite using reduced pressure and layer-by-layer (LBL) assembly, respectively. The microstructure and morphology of treated HNT were investigated using Fourier transform infrared spectroscopy and transmission electron microscopy. In addition, the anti-corrosion behaviors of the composite polyepoxy coating with inhibitor-loaded nano-containers BTA@HNT-2 were investigated using the electrochemical impedance spectroscopy and neutral salt spray test.

Test results showed that the LBL assembly structure of the halloysite nano-container makes the BTA@HNT-2 nano-container be controlled and sustained to release BTA, relying on the pH. Very importantly, the obtained nano-container is also responsive to temperature, owing to the thermosensitivity polyelectrolyte out-shell of the HNT. The result showed R_ct of the composite polyepoxy coating can be sufficient to maintain higher than 8.510E+7 Ω·cm² over 72 h of immersion test. Moreover, the artificial induced defects on the coating surface were sufficiently inhibited in the presence of BTA@HNT-2 nano-container in the polyepoxy coating.

Use of the BTA@HNT-2 as corrosion inhibitor nano-container, with good anti-corrosion property and dual-responsive to pH and temperature, offers a significant rout to prepare smart anti-corrosion coating for protecting metal substrate.

While the interest in alternative metalization processes for the manufacturing of printed wiring boards is extremely keen, the long‐term reliability of plated through holes fabricated with these electroless copper alternatives remains in question. However, during the last three years, significant process improvements have been made in the direct metalization process based on a patented dispersion of graphite. This paper will describe the technology in detail and present data on the reliability and versatility of the graphite based direct metalization process.

This review discusses the concept of edible nanocoatings (ENCs), the biomaterials used in the coating matrices, techniques of coating development, applications, challenges and safety regulations associated with nanotechnology in food products. These ENCs are capable of imparting increased shelf life, improved appearance, better physiological qualities and bioactive potentials such as antimicrobial and antioxidant properties. ENCs can be developed using the layer-by-layer method which forms multiple alternative layers adhered together primarily by electrostatic interactions.

Various keywords such as edible coatings (ECs), safety aspects and nanocoatings were used to search the literature from Google Scholar, Research Gate, ScienceDirect, Springer Link, Taylor and Francis and PubMed. After searching enough literature, 113 articles and research papers were examined, which provides the updated overview of different aspects of edible nano-coatings.

Consumers today are very much aware of the food quality and its safety. They demand food products with longer shelf life, which are minimally processed with natural or no preservatives. ECs based on biopolymers is an alternative technique, which is biodegradable and can be consumed as such without posing any safety risks. The emergence of nanotechnology in food processing has provided new insights to develop ECs at the nanoscale with improved mechanical and barrier properties

ECs are beneficial to consumers and to the environment. ECs have generated significant attention over years as an alternative to fossil-based plastics, considering their renewable and biodegradable features