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Coatings are subject to photoaging during their lifetime. Ultraviolet radiations absorbing additives (UVAs) and hindered amine light stabilisers (HALS) often are added to improve their performance. To improve performance of coatings, it is important to use optimum quantity of such additives.

In this study, hydroxyl‐terminated polyester was synthesised and then crosslinked using isophoronediisocyanate. These clear coats were then stabilised with various additives such as Tinuvin 1130, 123 and 292. The synergistic effect of these additives was also studied. The optical properties of coatings such as yellowness, whiteness and gloss of coatings were studied after exposing these coatings to various environments such as QUV weathering, direct UV and xenon arc.

The results showed that the coatings stabilised with combination of additives performed better than the unstabilised coatings as well as single additive coatings. A synergism was observed when using a combination of the UVAs and HALS.

The additives used were found to be compatible with the binder systems under study and was not found to be universally compatible with all resins.

UV degradation is a major concern in coatings both aesthetically and functionally. This study aimed at optimising the concentrations of UV stabilisers in order to increase the effective life time of exterior coatings.

UV stabilisers are routinely used in coatings for exterior applications. However, our aim was to optimise the concentrations of these additives in the coating so as to reduce the cost while keeping the performance of the coatings unaffected. By studying the synergy of the additives, we have also optimised their concentrations to further increase the life of the coatings.

Rheological Control Additives. Many additives to coatings affect the rheology of the composition so that application and storage properties are improved. A new rheological additive for emulsion polymers and water‐reducible resins has been described by Whitton and Masterson [Modern Paint & Coatings, November (1980) p. 33]. The authors point out that latex paints practically always require rheological additives if they are to have good application and stability properties. Without additives they are prone to dripping, sagging, and spattering as well as pigment settling, phase separation, and pigment flocculation. The most widely used rheological additives for waterborne coatings are cellulosic derivatives, and the authors estimate that 85 to 90% of latex trade sales coatings are thickened with additives such as hydroxyethylcellulose, methyl hydroxypropylcellulose, and methylcellulose. The disadvantages of these materials is that they are difficult to disperse which means that energy and time are consumed in grinding. Also, in automated pigment slurry systems the cellulosics require a large amount of water for dispersion. This limits flexibility in formulation. Also, the cellulosics can be attacked by enzymes although more expensive enzyme‐resistant forms are available.

This paper aims to achieve an anti-corrosive coating via uniform dispersion of nanoclay particles (montmorillonite) and polypyrrole (PPy) as a conductive polymer as well as their effects on the anti-corrosion features in the presence of the eco-friendly ionic liquids (ILs).

In this research, PPy with different forms of nanoclay were used. Moreover, ILs additive is used to enhance the better dispersion process of clay and PPy nanoparticles in the resin.

As a result, the IL additive in the formulation of nano-composite coatings greatly improves the dispersion process of clay and PPy nanoparticles in the resin. Due to its high compatibility with polyurethane resin and clay and PPy nanoparticles, this additive contains a high dispersing power to disperse the investigated nanoparticles in the resin matrix.

High polarity of ILs as well as abilities to dissolve both mineral and organic materials, they can provide the better chemical processes compared to common solvents.

IL abilities have not been discovered to a large extent such as catalysts and detectors.

ILs have been emerging as promising green solvents to replace conventional solvents in recent years. They possess unique properties such as nonvolatility, low toxicity, ease of handling, nonflammability and high ionic conductivity. Thus, they have received much attention as green media for various chemistry processes.

The simultaneous existence of clay, PPy and IL additive in the nano-composite coating formulation is responsible for the high corrosion resistance of the coating.

Automotive coating materials are very important items for this industry. However, their performance is limited by the use of excessive amounts of solvents in their formulations, whereas the emission of volatile organic solvents is against the widely ascending principle of green chemistry. Thus, this study aims to overcome this global problem to save the environment without affecting the properties and performance of the coating.

High solid content paint formulation for automotive applications has been designed with low amount of volatile organic solvents with the aid of a functionalized hyperbranched modifier.

It was found that the presence of a hyperbranched additive allows a high solid content to be designed and facilitate the processing, which indicates its liability to compensate the role played by excessive solvents amounts. In addition, the mechanical properties and physical characteristics of the modified coatings showed outstanding performance and preservation of clarity in comparison with the commercial counterparts.

A high solid content coating with facile processing and improved performance leads to cheaper price beside the positive impact on the environment considering the limited emission of volatile organic contents.

Limitation of the used volatile organic compounds in any industry helps to save the health of humans and keep the environment unaffected.

The use of functionalized hyperbranched additive to automotive coatings is a very promising additive for automotive coatings with optimized characteristics.

The purpose of this study is to develop a new protective coating formulation for industrial use, using benzodiazepine derivatives as double function additives.

Benzodiazepine’s derivatives of types (3–5) were prepared and confirmed by infrared, Mass, ¹H-Proton nuclear magnetic resonance (NMR) and ¹³C NMR spectra. The synthesized compound was physically incorporated in the alkyd paint formulation by pebble mill grinding until all particulates are smaller than 20 ums. The prepared coatings were applied by air spray on steel panels. The physical, mechanical characteristics, corrosion resistance and antimicrobial test of the prepared coatings were studied to evaluate the prepared compounds drawbacks.

The results of the mechanical and physical properties of the paint formulation revealed that the paint formulation incorporating benzodiazepines derivatives 3–5 performed best and improved corrosion-resistance and antibacterial activity tests.

In alkyd paint, heterocyclic compounds are the most used antibacterial additives. Other functionalities of these compounds, such as corrosion inhibitors, might be studied to see if they are suited for these applications.

Because of the activity of various benzodiazepine derivatives, which may be attributable to the presence of some function groups such as sulfonamide aromatic amino NH₂ group, and elements such as Sulphur, Nitrogen, Chlorine, in its chemical structure. As a result, paint compositions including these compounds as additives can be used as dual-purpose paint and for a variety of industrial applications.

The research demonstrates how a low-cost paint composition based on synthesized benzodiazepine derivatives 3–5 may be used as a dual-function paint for industrial use.

Paint‐films are very susceptible towards contact with hard object, i.e. they are subject to marring and scratching.

The preferable concentration of titanium carbide was optimized and added as an additive to the micro-arc oxidation electrolyte to produce a high corrosion-resistant coating on D16T aluminum alloy.

Ceramic coatings were deposited on D16T aluminum alloy by plasma electrolytic oxidation in alkaline silicate electrolytes with micron titanium carbide particle suspending at different concentrations. Influences of additive concentration on morphology, elemental and phase composition and corrosion resistance of doped PEO coatings were evaluated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and electrochemical methods, respectively.

Results revealed that suspending titanium carbide additives incorporated into ceramic coatings through discharging channels and chemically transformed into amorphous stage. The content of titanium in the doped coatings increased with the increasing concentration of suspending micron additive. Compared with the coating without particle addition, the corrosion resistance of the coating produced in 8 g/L titanium carbide suspension increased more than 20 times. The result indicated that the incorporation of titanium into the PEO coatings formed on the D16T aluminum alloy could effectively improve the corrosion resistance.

The mechanism of corporation of TiC and the mechanism of improving the corrosion resistance of the coating were proposed.

The purpose of this paper is to evaluate the efficiency of acrylated guar gum (AGG) as an additive in alkyd resin for improved mechanical properties and to optimize the results of such an addition.

For studying the effect of AGG on coating properties, guar gum was modified to various degrees of esterification and various compositions of alkyd systems were made by incorporating different concentrations of AGG. The mechanical and solvent absorption of the unmodified and modified alkyd systems were characterized.

The incorporation of AGG into alkyd coating showed significant improvement of mechanical properties over the unmodified one. The modification caused an additional crosslink site through its unsaturation which led to increased crosslink density without phase separation of additive from the alkyd system which was confirmed by SEM scans.

The reactive additive, AGG used in the present study was synthesised using acryloyl chloride. Besides, it could also be synthesised from methacryloyl chloride and the effect of methyl substitution on water and solvent absorption could be studied.

The method developed provided a simple and practical solution to improving the mechanical properties of alkyd coatings.

The method for enhancing mechanical properties of cured alkyd system was novel and could find numerous applications in surface coatings.

The purpose of this study is to investigate the effects of zinc dialkyl dithiophophates (ZDDP) and ash-less triphenyl phosphorothionate (TPPT) on hydrogen-free diamond-like carbon (DLC) coatings. For many years, ZDDP have traditionally been used in engine oils as antiwear (AW) and extreme pressure (EP) additives. However, additives containing sulfated ash, phosphorus and sulfur (SAPS) have a detrimental effect on the exhaust after-treatment device found on modern vehicles. Besides the automotive industry, DLC is also used in hydraulic applications where zinc-free and ash-less hydraulic fluids have gradually gained popularity in recent years.

The tribological tests were performed using a disk-on-cylinder tribometer, where the stationary hydrogen-free DLC-coated steel disk formed a line contact with an uncoated rotating steel shaft under lubricated conditions.

It was found that TPPT and ZDDP separately at a concentration of 1.0 wt% increased the amount of friction of the base oil by approximately four times. TPPT appeared more effective than ZDDP in minimizing wear on the DLC-coated surface. Also, primary ZDDP seemed to have a more detrimental effect on the DLC-coated surface compared to a mixture of primary and secondary ZDDP. With regard to surface roughness of the hydrogen-free DLC-coated surface, the values corresponding to a lubricant containing TPPT were lower than those obtained for a lubricant with ZDDP and a lubricant without any additive.

This is the first report on the effects of ZDDP and ash-less TPPT on the tribology of hydrogen-free DLC coatings.