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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.

The TNO Plastics and Rubber Research Institute, the TNO Paint Research Institute and the TNO Packaging Research Institute have merged into one new cooperation. named: TNO Centre for Polymeric Materials (CPM‐TNO).

This paper aims to focus the synchronous chemical conversion technology–based titanium/zirconium composite on 6061, 7075 aluminum alloys and galvanized steel.

The effects of pH, temperature, reaction time and other process parameters on the corrosion resistance of the three metal surface coatings were investigated by copper sulfate drop and electrochemical corrosion performance tests under a certain content of H2TiF6 and H2ZrF6. The surface morphology and element distribution of the conversion coating were analyzed by scanning electron microscope and X-ray photoelectron spectroscopy.

The results show that the optimal synchronization chemical conversion conditions of 6061/7075 aluminum alloys/galvanized steel are controlled as follows: H2TiF6 2.2 mL/L, H2ZrF6 1 mL/L, pH 3.9, conversion temperature 35°C and conversion time 120 s.

Multi-metals chemical conversion coating can be obtained simultaneously with uniform corrosion resistance and surface morphology. The presence of microdomain features in multiple metals facilitates simultaneous chemical conversion into coatings.

Various modifications of polyvinyl acetate emulsion wood adhesive were made and their performance evaluated in standard tests. The results are interpreted in the context of adhesion theories and the chemical structures of the polymers and wood. The adhesion of the polymers to wood and the cohesive strength of the polymers are the two predominant factors determining the performance of the adhesives. Adhesive strength in thermosetting resins is enhanced by irreversible chemical reactions that create extensive networks within the adhesive layer and strong bonds to the wood substrate, leading to strong and durable joints that passed all of the performance evaluation tests. Most of the PVAc emulsions exhibited good adhesive performance in the dry state, but failed in water soak and boiling water immersion tests since their adhesion and cohesion are mainly based on weaker physical interactions. Emulsions with (hard) core‐(soft) shell morphology and correspondingly high glass transition temperatures gave poor performance under all conditions.

This paper aims to present an underwater climbing robot for wiping off marine life from steel pipes (e.g. jackets of oil platforms). The self-adaption mechanism that consists of a passive roll joint and combined magnet adhesion units provides the robot with better mobility and stability.

Adhesion requirements are achieved by analyses of falling and slipping. The movement status on pipes is analyzed to design the passive roll joint. The optimized structure parameters of the combined magnet adhesion unit are achieved by simulations. An approximation method is established to simplify the simulations conditions, and the simulations are conducted in two steps to save time effectively.

The self-adaption mechanism has expected performance that the robot can travel on pipes in different directions with high mobility. Meanwhile, the robot can clean continuous region of underwater pipes’ surface of offshore platforms.

The proposed underwater robot is needed by offshore oil platforms as their jackets require to be cleaned periodically. Compared with traditional maintenance by divers, it is more efficient, economic and safety.

Due to the specific self-adaption mechanism, the robot has good mobility and stability in any directions on pipes with different diameters. The good performance of striping attachments from pipes makes the underwater robot be a novel solution to clean steel pipes.

The anticorrosion coatings used in marine and atmospheric environment are subjected to many environmental factors. And the aging failure has been puzzling researchers. The purpose of this study is to find the correlation between the initial aging of epoxy coatings and the typical marine atmospheric environmental factors.

The epoxy coatings were subjected to a one-year exposure in three typical marine atmospheres. Meanwhile, principal component analysis, linear regression and Spearman and gray correlation analysis were applied to quantify the environmental characteristics and establish correlations with the coating aging.

The results indicate that the coating will undergo macroscopic fading and chalking upon exposure to the marine atmosphere, while microscopic examination reveals holes, cracks and partial peeling. The adhesion performance and electrochemical properties of the coating deteriorated with prolonged exposure, coating aging mainly occurs with the generation of O-H bonds and the breakage of molecular chains such as C-N and C-O-C. The coating was most deeply aged after exposure to the Xisha, followed by Zhoushan and finally Qingdao. Environmental factors affect the photooxidative aging and hydrolytic degradation processes of coatings and thus coating aging. To further demonstrate the correlation between environmental factors and coating aging, principal component analysis was used. The correlation model between environmental factors and coating aging was subsequently obtained. The correlation model between the rate of coating adhesion loss (E) and the comprehensive evaluation parameter of environmental factors (Z) is expressed as E = 0.142 + 0.028Z. Meanwhile, the Spearman correlation analysis and gray correlation method were used to investigate the impact of each environmental factor on coating aging. Solar irradiation, relative humidity and wetting time have the highest correlation with coating aging, which are all above 0.8 and have the greatest influence on coating aging; wind speed and temperature have the smallest correlation with coating aging, which are about 0.6 and have the least influence on coating aging.

This paper establishes a correlation between typical marine environmental factors and coating aging performance, which is crucial for predicting the service life of other coatings in diverse environments.

Investigates the adhesion and corrosion performance of selected silanes in primed galvanised steel. For comparison HDG steel was also treated with a chromate‐free and a chromate‐containing pre‐treatment. All treated panels were painted with three different primers. Corrosion resistance and paint adhesion of the primed panels were studied. Surface energy of the panels was measured by the contact angle method and is reported in terms of the Lewis base component. The corrosion resistance of the panels depended on the combination of the silane and the primer. Vinyltrimethoxysilane (VS) and γ‐aminopropyltriethoxysilane (γ‐APS) treatments improved the corrosion resistance of polyurethane primed panels. γ‐ureidopropyltrimethoxysilane (γ‐UPS) and VS treatments improved the performance of polyester primed panels. A relationship between the base components and the prohesion test results of γ‐UPS and γ‐APS treated panels was found, which indicates that acid‐base interactions improve the adhesion between these two silanes and the primers. γ‐UPS and γ‐APS treated panels also achieved excellent results in the humidity test with all three polymer coatings.

The purpose of this paper is to present a new test method (tape peel method) to evaluate conformal coating adhesion to electronic assemblies.

The key issue for this method is the low cohesive force of conformal coatings, and hence selection of a supporting material to peel the coating from the substrate is critical. A suitable cloth material (35 per cent cotton +75 per cent polyester with 20 per cent open area) has been selected as a peel tape, and achieved the best bonding with coatings, and the smallest affect on the coating curing process. Using the tape, the peel force of the coating from the electronic assembly, can be measured quantitatively, and hence the adhesion performance of the conformal coating assessed.

The method was validated using different coating types, substrate materials (bare laminate with and without resist, copper clad laminate, and contaminated laminate material), assemblies and components. The results demonstrated that the tape peel test is a sensitive method for measuring coating adhesion on different materials found on PCB assemblies. Coating adhesion was found not to be effected by a wide range flux residues, but components and some resists presented a far greater coating challenge, with some coatings achieving very low adhesion values.

This new method for evaluating conformal coating adhesion to electronic assemblies will be of benefit to coating developers and users, and help to minimise adhesion failures in service. The test has been demonstrated to be sensitive to a number of process and material variables.

The aim of this work was to investigate which parameters affect the long‐term performance of coil coated galvanised steel sheet. Therefore, the paint adhesion and corrosion resistance of selected painted pre‐treated galvanised steel substrates were studied. The systems investigated included chromate‐free pre‐treatments and primers. The polymer coated panels were tested by using: T‐bend, combined cross cut and adhesion, prohesion and QUV‐A tests. The surface energy of the painted panels was determined by contact angle measurements and outdoor testing of the panels was also initiated. The test results showed that the primer was the most important parameter for painted metal alloy coated steel, but the long‐term performance of the system also depends on the compatibility of all four layers, i.e. substrate, pre‐treatment, primer and topcoat.