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The purpose of this study is to reduce the application of petroleum in automobile paint industry by replacing it with bio-based castor oil along with nano fillers to synthesize automobile base coat (BC).

Bio-based polyurethane (PU) coating applicable in automobile BC was synthesized by using modified castor oil incorporated with nano silica (NS) and titanium-based pigment particles. The influential characteristics of the coating was studied by carrying out cross-cut tape test, abrasion resistance, pencil hardness, lap-shear, thermo gravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis and acid, alkali and oil resistance tests.

Incorporation of NS particles, along with titanium-based pigment particles in optimized ratio into the paint matrix, increases the mechanical, chemical and oil resistance properties and hydrophobicity of the BC, and the findings are compared with the petro-based commercial BC.

There is no significant improvement in thermal properties of the paint matrix, and it is less thermally stable than the commercial BC.

The paint developed through this study provides a simple and practical solution to reduce the petro-based feed-stock in automobile paint industry.

The current work which reports the use of ecofriendly PU BC for automobile paint applications is novel and findings of this study are original.

This paper aims to access the protective function of hybrid sol-gel coatings deposited on 304L stainless steel substrate in silane solutions containing a mixture of tetraethoxysilane, methyltriethoxysilane and glycidyloxypropyltrimethoxysilane with different pH values during various immersion periods.

The 304L stainless steels coated through 10 and 30 s of immersion in the silane solutions with pH values of 2.1 and 2.8 were exposed to NaCl solution. The corrosion resistance of the coated substrates was studied through taking advantage of electrochemical noise method as well as atomic force microscopy (AFM), water contact angle and field emission-type scanning electron microscopy (FESEM) surface analysis.

The electrochemical current noise, PSD (I) plot, noise resistance and characteristic charge as parameters extracted from electrochemical noise method indicated the superiority of eco-friendly silane coating deposited on the substrate surface during 10 s exposure to the solution, due to the film uniformity and homogeneity as confirmed by FESEM and AFM. Moreover, immersion of the stainless steel in the silane solution with pH 2.1, characterized by higher hydrolysis ratio, led to more effective corrosion control in the NaCl electrolyte according to the results of electrochemical noise and FTIR measurements.

The noise resistance and characteristic charge as electrochemical noise parameters were only used in this research to evaluate the protective behavior of the water-based silane sol-gel coatings. Future studies should examine the correlation between electrochemical noise data and the parameters extracted from other electrochemical methods, e.g. electrochemical impedance spectroscopy.

The data obtained in this research may provide an effective approach based on electrochemical noise method to screen the silane sol-gel coatings for protection of metallic substrates against corrosion.

According to the literature, no report can be found studying the effect of immersion time on a silane solution, including glycidyloxypropyltrimethoxysilane, tetraethoxysilane and methyltriethoxysilane, as well as the silane solution pH on the corrosion resistance of 304L stainless steel in NaCl solution through electrochemical noise method.

This paper aims to enhance the barrier properties and active protection of a water-based silane coating on mild steel through nanoclay and zinc acetylacetonate simultaneously included into the formulation.

The corrosion protection performance of the silane sol-gel coatings with no additive, zinc acetylacetonate, nanoclay and nanoclay + zinc acetylacetonate was monitored using electrochemical impedance spectroscopy during 5 h of immersion in a sodium chloride solution. Moreover, the surface of coatings was analyzed using a field emission scanning electron microscopy equipped with an energy dispersive X-ray spectrometer (FESEM-EDX) and water contact angle measurements.

In electrochemical impedance spectroscopy analysis, the impedance at low frequencies, coating resistance and charge transfer resistance were the parameters considered which indicated the superiority of silane coating formulated with both nanoclay and zinc acetylacetonate. According to the results of FESEM/EDX and water contact angle measurements, the superiority was linked with the enhancement in the barrier properties in the presence of nanoclay, as well as function of the corrosion inhibitor at coating–substrate interface.

According to the literature, there is no research conducted to study the impact of the simultaneous use of nanoclay and zinc acetylacetonate on the barrier properties and active protection of an eco-friendly silane sol-gel coating including glycidyloxypropyltrimethoxysilane, tetraethoxysilane and methyltriethoxysilane on mild steel in a sodium chloride solution.

This study aims to focus on how reactive diluents with mono- and di-functionalities affect the properties of resin formulation developed from bioderived precursors. A hydroxyethyl methacrylate (HEMA) terminated urethane acrylate oligomer was synthesized and characterized to study its application in stereolithography 3D printing with different ratios of isobornyl acrylate and hexanediol diacrylate.

Polyester polyol was synthesized from suberic acid and butanediol. Additionally, isophorone diisocyanate, polyester polyol and HEMA were used to create urethane acrylate oligomer. Fourier transform infrared spectroscopy and ¹H NMR were used to characterize the polyester polyol and oligomer. Various formulations were created by combining oligomer with reactive diluents in concentrations ranging from 0% to 30% by weight and curing with ultraviolet (UV) radiation. The cured coatings and 3D printed specimens were then evaluated for their properties.

The findings revealed an improvement in thermal stability, contact angle value, tensile strength and surface properties of the product which indicated its suitability for use as a 3D printing material.

This study discusses how oligomers that have been cured by UV radiation with mono- and difunctional reactive diluents give excellent coating characteristics and demonstrate suitability and stability for 3D printing applications.

This study aims to develop multifunctional, namely, superhydrophobic, flame-retardant and antibacterial, coatings over cotton fabric, using casein as green-based flame-retardant and silver nanoparticles as antibacterial agent by solution immersion method.

The cotton fabric is first coated with casein to make it flame-retardant. AgNPs synthesized using Cinnamomum zeylanicum bark extract is coated over the casein layer. Finally, stearic acid is used to coat the cotton to make it superhydrophobic. X-ray diffraction, transmission electron microscopy analysis and ultraviolet-visible spectroscopy are used to investigate the produced AgNPs. The as-prepared multifunctional cotton is characterized by scanning electron microscopy, energy dispersive X-ray analysis and attenuated total reflection-infrared studies. Flame test, limiting oxygen index test and thermogravimetric analyzer studies have also been performed to study the flame-retardant ability and thermal stability of treated fabric, respectively. The antibacterial effect of the coatings is evaluated by disc-diffusion technique. Water contact angle is determined to confirm the superhydrophobic nature of cotton fabric.

The outcomes of this study showed that the prepared multifunctional cotton fabric had maximum contact angle of greater than 150° with good flame retardancy, high thermal stability, greater washing durability and high antibacterial activity against the growth of Pseudomonas aeruginosa and Acinetobacter indicus. Additionally, the as-prepared superhydrophobic cotton showed an excellent oil–water separation efficiency.

The trilayered multifunctional cotton fabric has limiting washing durability up to 20 washing cycles. Treated functional fabric can be used as an antibacterial, therapeutic, water repellent and experimental protective clothing for medical, health care, home curtains and industrial and laboratory purposes.

The study brings out the robustness of this method in the development of multifunctional cotton fabrics.

The purpose of this paper is to explore the application of triglycidyl resin (TGC) prepared from cardanol as partial replacement of conventional bis-phenol A (BPA) based epoxy resin for zinc rich primers (ZRPs).

The synthesis of new platform chemicals that are based on renewable resources has been accepted as a strategy to contribute to sustainable development due to the anticipated depletion of fossil oil reserves and rising oil prices. We prepared a tri-functional epoxy resin from cardanol which can be used as partial replacement of BPA based epoxy. The ZRPs were prepared using 50:50 ratio of TGC:BPA epoxy, and the coatings were evaluated for mechanical, chemical and anticorrosive properties.

The 50 per cent replacement of BPA based epoxy by TGC resulted in at par mechanical, chemical and anticorrosive properties as evaluated by various methods. The successful implementation can thus contribute to sustainable development by “green chemistry” route.

The prepared TGC resin in the current work was studied for application in ZRPs. This can also be explored for high performance coatings, adhesives and other engineering applications.

The TGC binder was prepared by simple two-step reaction. This can successfully be used as binder for coating application without any modifications.

A novel approach of using green and ecofriendly TGC resin as replacement of high cost BPA based epoxy was explored and can be implemented for numerous applications.

This study aims to synthesize a series of new anticorrosive pigments using a new technique called “core-shell”. This technique is based on depositing thin surface layer of expensive, efficient anticorrosive pigment on a cheap extender. This extender forms the bulk of the new pigments. The new pigments were constructed on cores of either waste silica fume or kaolin comprising 80-85 per cent of their chemical structure, and the ferrite shell was about of 20-15 per cent. Electrochemical studies were undertaken on two series of pigments for comparison between ferrites/silica fume and ferrites/kaolin pigment to show their performance, as the shells are different.

The different ferrites/silica fume and ferrites/kaolin pigments were characterized using different analytical and spectrophotometric techniques, such as X-ray fluorescence (XRF) and transmission electron microscopy (TEM). Immersion test and electrochemical impedance measurements were done in 3.5 per cent NaCl.

The tests revealed that paint films containing Sr ferrite/silica and Ca ferrite/kaolin were the most effective in corrosion prevention.

Silica fumes have a large array of uses. These pigments can be applied in various industries such as painting, wooding coating, anti-corruption coating, powder coating, architectural paint and waterproof paints. Treated kaolin can be applied in many industries besides pigment manufacture and paint formulations; it can be applied as a reinforcing filler in rubber, plastics and ceramic composites.

The new pigments are considered ecofriendly materials, because using them converts a waste product and a natural ore to useful marketable product, leading to reducing cost and saving the environment at the same time.

This paper aims to investigate the parametric study of addition of snail shell particles (SSp) and bath temperature on the properties of Zn-ZnO-SSp composites coating.

Bath temperatures of 60°C and 90°C and SSp of 0, 5, 10, 15, 20 and 25g were used in the electrodeposition. The microstructure, electrochemical, wear and hardness values of the coated samples were determined.

Highest coating thickness of 240 µm, 277 per cent improvement in hardness values, 66.67 per cent improvement of wear rate were obtained at bath temperature of 60oC and 15gSSp addition over that of the uncoated sample. There was improvement in corrosion resistance after composites coating. Maximum improvement in the properties was obtained at bath temperature of 60°C at 15gSSp addition.

It has been established in this work that bath treatment and SSps improved the properties of the developed coating.

To contribute to the identification of the parameters influencing the behavior of textile-reinforced concrete (TRC), the purpose of this paper is to investigate the flexural behavior of TRC-based plates under four-point bending notably designed in the context of sustainable development and the substitution of mortar components with natural and abundant materials.

An extensive experimental campaign was focused about two main parameters. The first one emphases the textile reinforcements, such as the number of layers, the nature and the textile mesh size. In the second step, the composition of the mortar matrix was explored through the use of dune sand as a substitute of the river one.

Test results in terms of load-displacement response and failure patterns were highlighted, discussed and confronted to literature ones. As key findings, an increase of the load-bearing capacity and ductility, comparable to the use of an industrially produced second textile layer was recorded with the use of dune sand in the mortar mix design. The designed ecofriendly samples with economic concerns denote the significance of obtained outcomes in this research study.

The novelty of the present work was to valorize the use of natural dune sand to design new TRC samples to respond to the environmental and economical requirements. The obtained values provide an improved textiles–matrix interface performance compared to classical TRC samples issued from the literature.

Functionalization of organic cotton fabrics (OCFs) by in situ deposition of chitosan reduced-stabilized silver nanoparticles (AgNPs). No other toxic chemicals used to warrant an ecofriendly synthesis protocol. Human toxicity of silver systematically avoided to use as textile clothing. Primary colors (nearly-red, yellow and blue) were imparted on OCFs via localized surface plasmon resonance (LSPR) of AgNPs. Decent mechanical properties and laundering durability in terms of antibacterial/fastness test improved mechanical properties.

Silver nanoparticles can be synthesized by using silver nitrate along with commercially available chitosan. Due to the surface LSPR property of silver nanoparticles, it exhibits versatile colors depending on the synthesizing procedures. The coloration occurs due to the electrostatic interaction between the AgNPs and chitosan-treated OCF. The nanotreated fabrics provide excellent mechanical properties with improved antibacterial effects.

X-ray fluorescence (XRF) analysis quantifies the developed materials in the substrates. Scanning electron microscopy (SEM) characterization indicates the appearance and morphologies of silver nanoparticles into the fabric surface after the coloration process. It proves that the treated cotton knit fabric exhibits the LSPR optical features of AgNPs. The antibacterial and mechanical properties confirm the improved functionality of products.

Improved mechanical properties, antibacterial performances and coloration effects on organic cotton substrates in terms of chitosan-mediated nanosilver are not yet studied.