Efficient strategy for hard nano-sphere usage: Boosting the performance of waterborne coatings

This work describes a study on the efficient use of waterborne hard-polymeric nanoparticles to improve properties of waterborne coatings such as: early hardness, blocking and resistance to fat. The waterborne nano-hard-spheres were synthesized by a special emulsion polymerization process enabling the use of low-surfactant concentration and high solid levels, and then blended with different commercial decorative binders. The colloidal stability of these bimodal systems was carefully analyzed, through rheology and dynamic light scattering analysis. Afterwards, different clear coatings were formulated, prepared, and applied onto different substrates to evaluate their properties. Results showed that the implementation of this waterborne technology enhanced the performance of the systems evaluated for decorative and industrial purposes.     

选购家装涂料的一些知识

介绍家装涂料的一些知识,选用家装涂料时应防止受骗上当。     

Tribological and electrochemical behavior of thick Cr-C alloy coatings electrodeposited in trivalent chromium bath as an alternative to conventional Cr coatings

Alternative process to hexavalent chromium plating, substitute materials and new designs are urgently needed owing to the requirement of “clean” manufacture. This comparative study was conducted to systematically investigate the tribological and electrochemical behavior of the Cr-C alloy coatings electrodeposited from a trivalent chromium bath and the hard Cr coatings electrodeposited from conventional hexavalent chromium bath, using reciprocating ball-on-disc tribometer and electrochemical analyzer. The electroplated Cr-C alloy coatings with thickness of 50 μm and acceptable quality that can be used for wear resistance as well as corrosion resistance purposes were produced successfully. The results show that the as-deposited Cr-C alloy coatings exhibited crack-free surface and amorphous/microcrystalline structure. The following heat treatment resulted in the cracked surface and the increase in hardness for the electroplated Cr-C alloy coatings. In contrast, the conventional Cr coatings exhibited cracked surface and their hardness decreased with the increase in annealing temperature. The electroplated Cr-C alloy coatings after heat treatment at 200 °C for 1 h exhibited better wear resistance than the conventional Cr coatings. In regard to the electrochemical behavior, the as-deposited Cr-C alloy coatings exhibited better corrosion resistance than the conventional Cr coatings. Therefore, the electroplated Cr-C alloy coatings are environmentally acceptable candidates to replace the conventional Cr coatings.     

Behaviour of intact and scratched phosphate coatings on zinc, zinc–nickel and mild steel in dilute sodium phosphate solution

Impedance measurements were performed at room temperature in a 0.005 M Na₂HPO₄ solution on steel and on electrodeposited Zn and Zn–12%Ni before and after phosphating. It was found that potential and impedance parameters (R _ct and C _d) for phosphated materials attained nearly steady values within about 20 min, indicating that this solution did not cause meaningful changes in phosphate coatings and that it could therefore be used for the quality evaluation of these coatings. On scratches in phosphate coatings on Zn or Zn–12%Ni phosphate deposits rapidly formed, probably owing to enhanced dissolution of the locally exposed substrates at the nobler potentials of the coated materials. This demonstrates that damaged coatings can easily recover on Zn substrates in a non-aggressive phosphate solution. It is suggested that the formation of phosphate deposits on bare metal amidst phosphate coatings should be taken into account in the porosity determination by chemical or electrochemical methods.     

Surface Composition and Topography of Electrodeposited Polypyrrole Coatings on Steel Substrates

Polypyrrole coatings were successfully electrodeposited on low-carbon steel substrates from aqueous oxalate solutions. The surface composition and topography of the polypyrrole coatings formed under different conditions were investigated by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The results show that the surface composition of the electrodeposited polypyrrole coatings basically reflects their bulk composition. Deposition of polypyrrole coatings on steel substrates also increased the surface roughness of the steel substrates.     

Surface Composition and Topography of Electrodeposited Polypyrrole Coatings on Steel Substrates

Polypyrrole coatings were successfully electrodeposited on low-carbon steel substrates from aqueous oxalate solutions. The surface composition and topography of the polypyrrole coatings formed under different conditions were investigated by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The results show that the surface composition of the electrodeposited polypyrrole coatings basically reflects their bulk composition. Deposition of polypyrrole coatings on steel substrates also increased the surface roughness of the steel substrates.     

我国内墙涂料现状与发展

介绍了目前我国内墙涂料的主要品种，叙述了内墙涂料的应用现状，并展望了我国内墙涂料的发展。我国内墙涂料的主要品种有丙烯酸酯乳液类、叔醋乳液类、聚醋酸乙烯乳液类和乙烯-乙酸乙烯酯（VAE）乳液类等，并有有光、丝光和平光等；所存在的主要问题是低端产品用量大，且这类涂料的配方因多是原材料供应商所提供，不尽合理。内墙涂料将主要朝着健康型和精细型发展，高颜料体积浓度的低成本涂料通过不断的努力研究也将逐步趋于合理。     

金属基体陶瓷涂料的研究与应用

简介了金属基体陶瓷涂料的应用及其优点。综述了适用于专门金属基体和通用金属基体的陶瓷涂料的最新进展。专用陶瓷涂料可以保护碳钢、不锈钢，也可以用于钛合金基体、Ni基高温合金和铌合金；通用陶瓷涂料按功能分为防腐蚀涂料、耐热涂料、耐火隔热防锈涂料、耐磨涂料及提高基体生物相容性的涂料。列举了重点开发的金属基体陶瓷涂料的领域。     

纳米复合水性仿幕墙外墙涂料

介绍了纳米复合水性仿幕墙外墙涂料的原料选择及配方设计，探讨了主要原材料对产品性能的影响以及关键制备工艺；研制出了一种具有高性能、高装饰性的纳米复合水性仿幕墙外墙涂料。     

船舶用氯化橡胶防腐蚀涂料的研制

利用中、长油度醇酸树脂、环氧树脂、钛白粉、附着力促进剂及耐紫外光助剂对氯化橡胶涂料进行改性研究,开发出一种适用于海洋环境的船舶、海上采油平台及钢构件用的高光氯化橡胶防腐蚀涂料,其涂层具有优异的装饰性、耐光老化性、耐盐雾性及附着力。     

电沉积耐磨复合镀层的研究与进展

综述了电沉积耐磨复合镀层的研究与进展,重点介绍了电沉积耐磨复合镀层的制备工艺、性能及其应用等.指出了目前所存在的问题,并对今后的研究提出了建议.     

功能涂料及其进展

功能涂料除应具备通用涂料的防腐作用和装饰作用外，主要是在特定的场合发挥特殊的功能，具有重要的应用价值。详细介绍了功能涂料的种类和特点，及其最新的技术进展。     

电镀合金的应用及前景展望

用电沉积法得到的合金镀层具有很多优异的特性，如良好的物理性能，优异的抗蚀性，美丽的装饰性、磁性，可焊性以及可进行热处理或可代替昂贵的金属等，主要综述了电沉积合金镀层的主要特性，应用及发展，并讨论了合金镀层的最新发展。     

Factors influencing the preferential orientations in zinc coatings electrodeposited from chloride baths

The influence of factors affecting the texture formation in zinc coatings electrodeposited from weakly acid zinc baths has been investigated, particularly those of cathodic current density, electrolyte additives and substrate texture type. Deposits showing no preferential orientations were obtained from a chloride bath with no primary inhibitors, with which the earlier theory on autoinhibition caused by colloidal zinc hydroxide in sulphate electrolytes was confirmed. The addition of synthetic inhibitors resulted in the production of various types of texture according to the electrolysis conditions and substrate texture type. Cone fibre texture coatings were obtained on cold worked copper cathodes and at lower cathode densities. A simple fibre texture was produced only at higherD _c values. The preferential orientation of electrodeposited zinc coatings on electrolytic nickel textured substrates depended on whether the electrochemical conditions or the textured substrate was the dominant factor. Various simple fibre textures were formed on electrodeposited amorphous Ni–P alloy substrates irrespective of the electrochemical conditions. Within a relatively short time after the completion of the electrodeposition of zinc coatings from chloride or sulphate baths, recrystallization processes were observed at room temperature.     

Flash IR pre-curing of the decorative layer in metal-flake powder coatings

Metal-flake powder coatings are a special class of metallic paint finishes composed of two superimposed layers: a pigmented decorative base coat and an overlaying transparent protective top coat. In the present investigation, a novel curing procedure for such bilayer coatings is proposed. Flash IR pre-curing of the base coat promotes the formation of a surface diffusion barrier and limits movement of the decorative pigments and metal flakes around their initial positions. Oven baking after deposition of the top coat then completes curing of the bilayer coating. The influence of the IR intensity and irradiation time on the final properties of bilayer coatings was investigated. The visual appearance, surface morphology and scratch resistance were evaluated. Experimental findings revealed that the hybrid IR/oven baking curing procedure is a viable method for obtaining bilayer powder coatings with outstanding properties in a shorter processing time and with considerable energy savings.     

乳液型紫外光固化聚氨酯丙烯酸酯的涂膜性能及其影响因素

合成了一系列乳液型紫外光(UV)固化聚氨酯丙烯酸酯,针对其涂膜性能进行研究,考察了辐射时间、膜厚、光引发剂用量、分子结构等因素对涂膜性能的影响;通过对各种影响因素的研究,得到了具有优良的涂膜性能和装饰性的乳液型UV固化聚氨酯丙烯酸酯,附着力在0~1级,正反耐冲击性都在50 cm以上,铅笔硬度可以达到3H以上。     

脉冲与直流电沉积RE-Ni-W-P-SiC复合镀层性能研究

采用脉冲与直流电沉积，研究了RE—Ni—W—P—SiC复合镀层的性能。结果表明：在相同的条件下，采用脉冲电流得到的复合镀层比直流电流得到的镀层有更高的硬度、沉积速度，同时耐磨、耐蚀性也得到提高。     

Bioactive glass coating using aerosol deposition

This work demonstrates the successful deposition of bioactive glass (BG) 45S5 coatings on various metallic and ceramic substrates at room temperature under low vacuum condition by using aerosol deposition (AD). This room temperature and particle impact consolidation-based deposition method enabled us to deposit well-adhered and dense BG coatings directly on metallic and ceramic substrates. In vitro tests with human osteoblast-like cells on substrates with a 45S5 BG coating demonstrated high cell activity on the surfaces. All tested materials exhibited high in vitro biocompatibility as no inhibition in cell proliferation could be observed. The utilization of AD process for achieving non-crystalline BG coatings is promising for practical bio-medical applications, e.g., bioactive coatings on bioinert metallic and ceramic substrates.     

多彩仿外墙砖涂料的制备

多彩仿外墙砖涂料以改性有机硅丙烯酸乳液为基料,天然石英砂为主要填料,辅以多功能助剂等制备而成,具有抗污、耐候及超耐久等性能,外观上达到外墙砖的装饰效果,形象逼真、高贵质感、施工性优,是一种最新型高性能、高装饰性墙体涂料。     

Electrochemical impedance spectroscopy; a tool for organic coatings optimizations

Electrochemical impedance spectroscopy (EIS) was applied to the optimization of automotive electrodeposited coatings, container interior coatings and industrial maintenance coatings. The electrochemical impedance data were used to predict corrosion protection, film porosity, solution absorption into the coatings and film delamination properties. Variables such as resin contents, crosslink densities, cure temperatures, and solvent types and contents were evaluated for these various types of coatings. In general the electrochemical impedance data correlated well with conventional exposure tests results such as salt fog, cyclic scab corrosion and delamination tests. The impedance spectra permits a rather rapid (15–75 min per sample) assessment of the film's characteristics even when no visually observable changes have occurred. Electrochemical impedance spectroscopy provides a technique to optimize coatings while reducing the time of coating evaluations and gives insight into the chemical and physical properties of the coatings.