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The purpose of this paper is to study the electrochemical, mechanical and thermal characteristics of polyester – epoxy coating systems using electrochemical impedance spectroscopy (EIS), pull-off test and differential scanning calorimetry (DSC). These are very important properties to evaluate the performance of a coating system. Proper measurement and analysis techniques are needed for a proper evaluation of these properties to ensure the coating performance.

Different ratios of polyester and epoxy resins have been blended to formulate good anticorrosive, mechanically strong and thermally stable binder coating system. EIS, pull-off test and DSC were used to evaluate these properties.

The sample containing 90 wt.% polyester exhibited the best corrosion resistance from the beginning until the end of exposure time. The value of corrosion resistance (R_c) obtained on the 30th day of exposure was found to be 2.89 × 108 ohm cm⁻². The glass transition temperature (T_g) was found to be increasing with the incorporation of epoxy to the binder system. The result from pull-off test showed the best adhesion with the sample containing 90 wt.% polyester which also has the lowest T_g promoted better adhesion properties.

The curing time must be reduced for practical applications.

Hybrid coatings systems have been formulated. This paper discusses on the highest coating resistance obtained polymer-substrate mechanical properties and thermal characteristic of the polyester/epoxy binder resin using DSC.

This paper aims to analyse the coating behaviour in corrosion environment as well as to evaluate the best percentage amount of copper oxide and copper needed for organic coating in order to prevent the corrosion degradation. Electrochemical impedance spectroscopy (EIS) studies have been conducted in order to evaluate the corrosion performance of polyester-epoxy-copper oxide and polyester-epoxy-copper coating systems.

The availability of this modem instruments is used to obtain impedance data as well as computer programs to interpret the results that made the technique popular. In addition, EIS is well suited to the study of polymer-coated metals.

The results showed that samples containing 25 weight per cent of copper oxide and copper (90P25CuO and 90P25Cu) obtained the excellent corrosion properties from the first day up to 30 days of NaCl immersion. The highest corrosion resistance values obtained by 90P25CuO and 90P25Cu on the 30th day were 7.107 × 108 O and 5.701 × 108 O, respectively, with lower double layer capacitance of 1.407 × 10⁻⁹ Farad and 3.935 × 10⁻⁹ Farad, respectively. Moreover, the water uptake gained by these two coating samples was the lowest at the end of immersion, which was 0.0084 for 90P25CuO and 0.1592 for 90P25Cu, showing that the sample has good corrosion performance.

This paper discussed on the highest corrosion resistance, double layer capacitance and the water uptake of the copper (Cu) and copper oxide (CuO) coating system obtained from the EIS measurements.

The purpose of this work is to investigate the influence of curcumin dye natural colorant on adhesion, mechanical, thermal and electrochemical properties of blend poly (methyl methacrylate) (PMMA) – acrylic polyol.

Extracted curcumin yellow dye colorant from Curcuma Demostica was mixed with PMMA‐acrylic polyol blended polymer in the volume ratios of 9:1, 8:2 and 7:3. The mixtures were applied on pre‐treated cold‐roll mild steel panels. All of the paint coating samples were subjected to potential time measurement (PTM), rapid impact deformation, differential scanning calorimetry (DSC), cross hatch and Fourier transform infrared spectroscopy (FTIR) tests.

The addition of curcumin dye colorant was able to improve the adhesion, flexibilities and resistance against electrolytes penetration of the blended poly (methyl methacrylate) (PMMA) – acrylic polyol polymer paint system. Cross hatch test studies showed that high amount of curcumin dye colorant (AP30 paint system) had the lowest peel‐off coating area from the substrate. The FTIR test had confirmed the high concentration of hydroxyl group in the AP30 sample. The hydroxyl group was able to promote hydrogen bonding between coating substrate interface. The AP30 sample had the highest coating flexibilities when tested with rapid impact test. This was due to the lowest glass transition value T_g which indicated lowest cross linking density in the coating molecules structure. In the PTM test, AP30 paint system had shown the highest rate electrolytes penetration within the AP sample.

The composition of curcumin dye colorant in the polymer blend is limited from 10 percent to 30 percent pigment volume concentration. Increasing the amount of lawsone pigment will result inhomogeneous mixtures.

The AP paint system is suitable for interior applications. This paint system has to be mixed with suitable additive materials to improve its performance for exterior purpose.

Corrosion is an important problem to be taken care in terms of economic and ecological aspects. The aim of this paper is to identify the methods of protection and selection of materials for corrosion protection.

A novel attempt has been made to formulate a hybrid composite paint system using silicone (S2) and polyester (P3) resins. These resins have been blended in different weight ratios to develop binder for protection coatings. Cross‐hatch test, impact resistance test, thermal characterization, impedance measurement and potential‐time measurement were conducted on binder coated steel panels. Heat resistance test was carried out using ASTM D2485 standards.

The results showed that physical and mechanical properties of the coatings have been improved by the addition of silicone into the polyester matrix. The binder system developed using 50 wt per cent polyester and 50 wt per cent silicone showed good physical, mechanical properties and high thermal resistance. The maximum coating resistance of the coatings after 30 days exposure was found to be 9.7×10⁶ Ω and the coating can withstand high temperature up to 473 K.

The development of different types of coatings will be useful to achieve higher protection performance. The combinations of different resins and pigments have to be analysed and selected suitable compositions.

The objective of this study is to develop coating system with different resins to achieve better performance and reduce the cost of paint materials. It may be useful for the industries to move forward with new formulation using multicomponent coating materials. A critical combination of the above resins offers better protection for steel structures from high temperature corrosive environments.

The formulation of coating material using two different resins and a single curing agent is a novel approach in this research. This type of research will open new ideas of formulating different coatings using various types of resins. In high temperature corrosion environment, the coatings which is commonly used is silicone based and the price of the raw material is very high therefore to reduce the cost of the raw material, the silicone resin is being blended in different ratios with organic resin to obtain an optimum ratio which can be applied to overcome high temperature corrosion on steel panels.

The purpose of this paper is to investigate the heat resistance properties of silicone‐acrylic hybrid system on cold rolled mild steel panel.

The presence of Si−C bonds in hydroxyl functional solid phenyl‐methyl silicone should be able to improve heat resistance properties of silicone‐acrylic polyol coating. Different weight ratios of silicone resin and acrylic polyol resins were blended in order to obtain the composition for optimum thermal properties. Thermal stability of silicone based protective coatings has been investigated by means of potential time measurement (PTM) and electrochemical impedance spectroscopy (EIS) techniques.

The blending of silicone intermediate resin with acrylic polyol resins. The coating consisting of 30 per cent silicone resin and 70 per cent acrylic resin showed significant improvement of heat resistivity compared to pure acrylic polyol resins on cold roll mild steel panels. This study demonstrates an interesting correlation between PTM and EIS studies.

Findings may be useful in the development of heat resistant paints.

The blending method provides a simple and practical solution to improve the heat resistance properties of acrylic polyol resins.

Durability and functionality of the coating, critically depend on the strength and adhesion properties of the materials. This may be a useful source of information for the development of organic‐inorganic coatings.

The purpose of this paper is to develop a new water based coating system composed of poly(acrylamide‐co‐acrylic acid) and anthocyanin colourant extracted from Hibiscus sabdariffa L. and characterise the system.

Anthocyanin from Hibiscus sabdariffa L. (roselle) calyxes was extracted using optimised water extraction method with ratio of calyxes to water being 1:2. UV‐Vis absorption spectroscopy was conducted on the anthocyanin extract to monitor its degradation. Poly(acrylamide‐co‐acrylic acid) was mixed with the extracted anthocyanin solution in two different weight ratios. The mixtures were coated on glass substrate and let to cure for approximately one day. FTIR spectroscopy was conducted on the samples to determine their functional groups and identify the compounds in the samples. Cross hatch test was performed on the samples to determine the adhesion properties. Thermal degradation of the samples was determined through thermogravimetric analysis. Surface roughness of the samples was studied by atomic force microscopy. Colour stability was determined before and after UV irradiation.

Anthocyanin pigment from roselle extracted with water was found to be stable with 6.0 per cent drop in absorbance value over the 15 day period. The reaction rate was found to be 0.000181 h⁻¹, and the half life was calculated to be 3,850 hours. Better adhesion of the samples to the glass substrate was due to the higher concentration of poly(acrylamide‐co‐acrylic acid). Thermogravimetric analysis revealed similar thermal stability of the samples. Surface roughness study revealed that sample with higher anthocyanin content has higher surface roughness. Colour stability of the 20PBR was found to be better than 10PBR.

Usage of poly(acrylamide‐co‐acrylic acid) as coating is limited by its weak water resistance property. Improvement could be made in this direction for future applications.

Mixture of water‐based polymer and anthocyanin colourant from roselle has been developed into coating for the first time. Commercialisation is possible if more research is conducted towards water resistance property of poly(acrylamide‐co‐acrylic acid), storage condition for the pigment and coating, and mass production of the pigment.

Incorporation of anthocyanin pigment into water based coating is the first of its kind.

The purpose of this paper is to improve the strength and adhesion properties of modified acrylic polyol resin using epoxy polyol resin (DEGBA).

The hybrid systems were prepared by blending acrylic resin with epoxy polyol resin (Diglycidyl Ether of Bisphenol‐A, DGEBA) and polyisocyanate resin as hardener in various weight ratios with xylene as a solvent. The samples were applied on the pre‐treated cold rolled mild steel panels. The mechanical property of the blend has been evaluated using rapid impact tester (Sheen 806/40) and adhesion tester (Sheen Cross‐Hatch 750). Intended panels were checked for cracks using Dino‐Lite and Pinhole detectors (Elcometer 270/4). Crossed panels were observed for damages using digital polarized microscope (Dino‐Lite, AM413ZT). The thermal properties were studied using thermal analysis system (TGA TA‐Q500, DSC TA‐Q200).

The modification of acrylic polyol resins using DGEBA showed significant improvement of toughness compared to pure acrylic polyol resins. The blending systems with 10 wt percent of DGEBA and 90 wt percent of acrylic resin showed good adhesion and impact resistance properties on mild steel substrate.

The hybrid coating system has contributed to the basic conceptual understanding of the corrosion protection property, focusing mainly on recent research available.

The blending method provided a simple and practical solution to improve the toughness of acrylic polyol resins.

The method for enhanced toughness of cured acrylic was novel and functionality of coating critically depends on adhesion between the coatings and underlying metal substrate.

The purpose of this study is to develop anti-corrosion coating systems using disposable waste materials. The dissolved polyethylene terephthalate (PET) has been blended with epoxy resin and stoichiometrically cured with a polyamide resin.

Glycolysis process was found to be the most optimum candidate to dissolve PET. The developed coating systems were characterized by Fourier transform infrared spectroscopy for confirmation of the molecular bonding structures. The mechanical properties were characterized by performing pull-off test and cross hatch test for mechanical properties on the coated panel. Also, the glossiness test was used by reflecting light on the coated surface. The corrosion protection performance of the coated mild steel panels was examined using electrochemical impedance spectroscopy. Furthermore, the wettability of the developed coating systems was evaluated by using water contact angle technique.

It was observed that the coating system which contains 10 per cent of dissolved PET (S2) showed the highest adhesion and corrosion protection properties.

Recyclable PET bottles have outstanding chemical properties, adhesion properties, low cost, low permeability to gases and solvents making it suitable as a coating with superior barrier properties.

The paper aims to investigate the effect of Degussa P-25 Titanium Dioxide (TiO₂) nanoparticles on hydrophobicity and self-cleaning ability as a single organic coating on glass substrate.

Two methods have been used to enhance the hydrophobicity on glass substrates, namely, surface modification by using low surface energy isooctyltrimethoxysilane (ITMS) solution and construction of rough surface morphology using Degussa P-25 TiO₂ nanoparticles with simple bottom-up approach. The prepared sol was applied onto glass substrate using dip-coating technique and stoved in the vacuum furnace 350°C.

The ITMS coating with nano TiO₂ pigment has modified the glass substrate surface by achieving the water contact angle as high as 169° ± 2° and low sliding angle of 0° with simple and low-cost operation. The solid and air phase interface has created excellent anti-dirt and self-cleaning properties against dilute ketchup solution, mud and silicon powder.

Findings will be useful in the development of self-cleaning and anti-dirt coating for photovoltaic panels.

Sol method provides the suitable medium for the combination of organic–inorganic network to achieve high superhydrophobicity and optimum self-cleaning ability.

Application of blended organic–inorganic sol as self-cleaning and anti-dirt coating film.

The purpose of this study is to develop a protective coating system on mild steel panel incorporating epoxidized natural rubber with acrylic polyol resin.

In this work, a novel attempt is made to develop binder coatings using epoxidized natural rubber-based material and an organic resin (acrylic resin) for corrosion protection on metal substrate. Seven different samples of multifunctional coatings are developed by varying the compositions of epoxidized natural rubber (ENR) and acrylic resin. The properties of the developed coatings have been characterized using analytical methods such as Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). EIS has been carried out for 30 days to evaluate the corrosion resistance after immersing into 3.5 wt.% of sodium chloride. Cross hatch cut tester (CHT) has been used to study the adhesive properties. UV–Visible Spectroscopy (UV–Vis) was also used to assess changes in the coating-film transparency of the natural rubber-based coating systems in this study.

The developed coatings have formed uniform layer on the substrate. CHT results show excellent adhesion of the coatings. Higher concentrations of ENR have higher transparency level, which reduces when the acrylic concentration increases. FTIR analysis confirms the crosslinking that occurred between the components of the coatings. Based on the impedance data from EIS, the incorporation of natural rubber can be an additive for the corrosion protection, which has the coating resistance values well above 108Ω even after 30 days of immersion.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resin with epoxidized natural rubber. There is still improvement needed for long-term applications.

The work has been conducted in our laboratory. The combination of natural rubber-based materials and organic resins is a new approach in coating research.