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The purpose of this paper is to evaluate the performance of polypropylene glycol (PPG), as a corrosion inhibitor for aluminium corrosion in 0.5 M H₂SO₄ solution at 303-333 K and the effect of addition of iodide ions on the corrosion inhibition efficacy of PPG.

The corrosion inhibition performance of PPG alone and on addition of iodide ions in the acid medium was evaluated using weight loss and electrochemical [electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR) and potentiodynamic polarization (PDP)] methods as well as surface analysis approach at 303-333 K. The morphology of the corroding aluminium surface without and with the additives was visualised using scanning electron microscopy (SEM). The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.

Results obtained showed that PPG moderately retarded the corrosion of Al in 0.5 M H₂SO₄ solution. Addition of KI to PPG is found to synergistically improve the inhibitive ability of PPG. From the variation of inhibition efficiency, K_ads, and E_a, with rise in temperature, physisorption mechanism is proposed for the adsorption of PPG and PPG + KI onto the Al surface in 0.5 M H₂SO₄ solution. Polarisation results showed that PPG and PPG + KI acted as mixed type inhibitor. The adsorption of PPG and PPG + KI, respectively, onto the metal surface followed El-Awady et al. adsorption isotherm model. SEM and water contact angle analysis confirmed the adsorption of PPG and PPG + KI on Al surface.

The research is limited to aqueous acid environment in aerated condition, and all tests were performed under static conditions.

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

This paper details the use of isophthalic acid and trimellitic anhydride for the design and production of water reducible alkyd coatings. The performance of these systems is equal to or better than conventional solvent based systems. The use of special processing, compounding or application equipment is not required for the production of these coatings, however, the raw materials must be carefully selected to ensure optimum performance. Both water reducible alkyds and water reducible acrylated alkyds for air drying and force cured applications will be discussed. Coatings manufacturers in the United States have commercialized these systems for applications varying from air dry implement enamels to interior can coatings.

The purpose of this study is to develop a additive manufacturing (AM) process for the fabrication of ionic polymer–metal composite (IPMC) devices with complex designs that would be time-consuming to replicate using conventional manual methods. These IPMC devices have considerable potential in electroactive polymers (EAPs) and soft actuators.

This paper presents a novel three–dimensional (3D) AM technique to develop IPMCs. Digital light processing (DLP) fabrication of soft EAPs was undertaken using a vat-based AM method, followed by deposition of cost-effective outer silver electrodes.

DLP-fabricated devices were compared to conventional Nafion™-117 devices. DLP layer-by-layer fabrication of these devices allowed for good resolution for a range of printed objects. Electrical actuation of the DLP-produced IPMCs showed tip displacements of up to 3 mm, and greater actuation was seen in the presence of lithium rather than magnesium cations. The IMPCs showed good ion exchange capacities, while electrochemical analysis showed the reversible formation and removal of AgCl layers in addition to ion movement.

The AM of these devices allows for rapid prototyping as well as potential use in the development of multiple degrees of freedom actuators and devices.

An original resin formulation was developed for DLP 3D printing. This formula is chemically distinct from the conventional Nafion™-117 membranes that can be purchased. Additionally, this method allows for the manufacture of complex objects that would be difficult to machine by hand. These findings are of value to both the fields of polymer chemistry and AM.

Lauroyl peroxide can be produced by reaction of lauroyl chloride with hydrogen alkali metal peroxides, e.g. it can be produced by treatment of lauroyl chloride with hydrogen peroxide and potassium hydroxide. It has also been prepared by reacting a mixture of lauroyl chloride, lauric anhydride and phosphorous trichloride in benzene, with a mixture of hydrogen peroxide, water, sodium phosphate and caustic soda. It can be dried in the form of an emulsion by centrifuging.

An article by Carra and Cavallotti [L'Industria della Vernice, 30, 11 (1976) p. 9] discussed the fundamental aspects of corrosion protection by organic coatings with emphasis on two parameters, adhesion and permeability to corrosive agents. Included is a mathematical treatment of the thermodynamics of adhesion.

A series of novel halamine polymers known as pyrimidinone biocidal polymers were prepared by reacting poly‐4‐vinylacetophenone with urea and benzaldehyde to form 1H,3H,6H,‐4(4′‐polystyreno)‐6‐phenyl‐pyrimidin‐2‐one, which on chlorination yielded 1Cl,3H,6H,‐4(4′‐polystyreno)‐6‐phenyl‐pyrimidin‐2‐one. The same reaction was also carried out using the derivatives of benzaldehyde such as p‐nitrobenzaldehyde and p‐methoxybenzaldehyde under the same reaction conditions. .

The coatings industry is based on a large number of scientific principles. To be sure, it developed both in ancient and modern times without regard to these. But once an empirical body of knowledge was built up, it became obvious that theoretical underpinnings were not only desirable but necessary if progress were to be made. What are some of the scientific principles which govern coatings technology? Film formation is certainly one. What causes a film to form, and what affects the properties of a film such as cohesion, adhesion, gloss, flexibility, permeability, impact resistance, and a dozen other characteristics? The problem of understanding film formation became all the more important with the advent of waterborne paints, for polymer particles suspended in water are not nearly as prone to form films as are polymer solutes in a solvent.

This paper describes the development and the numerical analysis of an electrochemical model for the analysis of a novel polymer/metal composite actuator. A general continuum model describing the transport and deformation processes of these actuators is briefly presented, along with a detailed description of the simulation scheme used to predict deformation, current, and mass transport. The predictions of the model are compared with experimental data, indicating a significant role of water transport in the large‐scale deformation. Comparison of the simulations and experimental data showed good agreement confirming the central role of water transport in the deformation process. For the sake of completeness the fabrication process and testing apparatus are also described.