超细涂料色浆对电泳漆涂装性能的影响

通过超声法制备了超细涂料色浆,并将其应用到阴极电泳漆中。考察了超细化前后涂料色浆的平均粒径、Zeta电位的变化,比较分析了超细涂料色浆与普通涂料色浆用于阴极电泳漆时漆液稳定性、漆膜沉积量、颜色深度、外观的区别。实验结果表明:超细涂料色浆的平均粒径仅为196 nm,Zeta电位为30 mV且分布均匀。用超细涂料色浆配制的电泳漆液具有较高的离心稳定性。相比于含普通涂料色浆的阴极电泳漆,含有超细涂料色浆的阴极电泳漆的漆膜的电沉积量稍高,而且更加均匀、平整、细腻。     

阴极电泳涂料的发展趋势

阴极电泳涂料作为一种环保型的水性涂料,具有广阔的应用前景。介绍了电沉积原理,阴极电泳涂料树脂的特点以及阴极电泳涂料的优越性。概述了国内外阴极电泳涂料的现状及需求,重点介绍了几类目前发展较快的阴极电泳涂料,同时指出了阴极电泳涂料今后的发展趋势。     

阴极电泳涂装的应用及发展

阴极电泳涂料具有高耐候性、高耐蚀性、高透明度、装饰性好和环保安全且对金属基体无腐蚀性等特点而广泛应用于金属表面涂装处理。概述了国内外阴极电泳涂装的发展状况,并介绍了几种特殊阴极电泳涂料,如紫外光固化电泳涂料和自分层阴极电泳涂料等。阐述了阴极电泳的特点和在涂装行业中的应用以及电泳涂料发展的最新动态。     

High-build soluble matrix antifouling paints based on vinyl resin

The aim of this work was to formulate and evaluate high-build, soluble matrix antifouling paints showing reduced solvent retention in the film and sufficient bioactivity to protect structures submerged in sea water for long immersion periods.

The variables analyzed were binder composition, pigment content, toxicant type and thixotropic agent content.

Binder dissolution in sea water was achieved by employing WW rosin or calcium resinate; the control of the binder dissolution rate was achieved by using a vinyl resin as a cobinder. The paints were formulated with pigment volume concentrations of 40 and 45%; red cuprous oxide and triphenyl tin fluoride were used as the main toxicants. The rheological additive employed was hydrogenated castor oil at levels of 2.0 and 2.5 wt.% in the paint.

The bioactivity of the antifouling paints was determined in the natural environment (30 month immersion in sea water).     

耐磨阴极电泳涂料的研究

利用专用水性阳离子颜料分散树脂,选择环保型颜料、助剂和耐磨填料,设计出耐磨阴极电泳涂料的色漆配方和分散工艺.采用PTFE乳液对传统乳液进行改性,当PTFE乳液用量为30%时,获得了具有优异耐磨性能的阴极电泳涂料.     

Titania pigment particles dispersion in water-based paint films

The distribution of titanian pigment, in dry water-based paint films in the presence of polymeric dispeersants containing different functional groups was investigated. The polymeric dispersants chosen were polyacrylic acid and polyacrylamide momo-and copolymers modified with hydroxyl and/or carboxylate groups. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were used to assess the distribution of the titania pigment particles in the surface and bulk, respectively, of the paint films, which was then compared to the gloss and surface roughnes of these films. In the absence of dispersant, the pigment distribution in the paint film was not uniform and relatively large pigment aggregates appeared at the surface, resulting in a rough surface and low gloss value. All dispersants both decreased surface roughness and increased the gloss of the dry paint film, with the dispersant type considerably enhancing the pigment dispersion in the dry paint film, in agreement with results obtained in aqueous pigment suspensions. In the presence of polyacrylamide homopolymer, the paint gloss increased slightly and further increased with the hydroxyl-modified polyacrylamide copolymer. The paint gloss was highest in the presence of polyacrylic acid or carboxylate/hydroxyl-modified polyacrylamide.     

Anti-fouling paints. I. Theoretical approach to leaching of soluble pigments from insoluble paint vehicles

A theoretical approach to the problem of how contact leaching anti-fouling paints work is discussed; a possible mechanism is selected and applied to an idealised model of a paint film. A precise mathematical treatment is then attempted of the relationship between the leaching rate, the physical properties, and if applicable the chemical properties of the envisaged paint film and its environment. A mechanism previously proposed has been examined by this method. An equation is derived for an idealised paint film relating the leaching rate to the physical properties of the paint film and the leachate. It is assumed that the rate of solution of a soluble pigment from an insoluble vehicle is dependent only on the physical properties of the paint film and the diffusion of the solvated pigment through the exhausted matrix and the diffusion layer of leachate in direct contact with the surface of the paint. An equation is derived for an idealised paint film which relates the leaching rate to some physical properties of the paint film and of the leachate. The equation is shown to predict qualitatively the effect of most variables known to affect the leaching of contact leaching paints. Some evidence is given to support the quantitative prediction of the relationship between the pigment volume content and the initial leaching rate, the effect of dissolved pigment in solution on the leaching rate, the increase in leaching rate for a given temperature increase, and the effect of velocity of flow past the surface of the paint film. This method of approach would appear to be applicable to mechanisms and models bearing a closer resemblance to practical anti-fouling paints. However, the mechanism proposed appears sufficiently well substantiated to be employed in the design of leaching experiments and their application to more practical problems, such as the formulation of anti-fouling paints. The need of a more rigorous approach to the design of leaching experiments is indicated.     

Corrosion rates of steel embedded in cement pastes

Dynamic polarization techniques were used to estimate the corrosion rates of steel embedded in cement paste made with different binder systems. A corrosion model is proposed. The corrosion rates were determined by employing the Evans diagrams constructed from cathodic polarization curve of steel embedded in chloride free cement paste and anodic polarization curve of steel embedded in cement pastes containing chloride. Within the limitations of the adopted experimental conditions and sample configuration, the preliminary results indicate that corrosion rates of steel embedded in blended cement pastes generally fall within the range shown by steel embedded in portland cement pastes.     

有机锡对双酰胺改性环氧聚氨酯树脂阴极电泳漆的影响

采用环氧聚氨酯树脂作为主体树脂,有机锡(二辛基氧化锡,DOTO)为催化剂,制备了阴极电泳漆,并对电泳原漆和漆膜的物理化学性能进行了考察。实验结果表明:电泳原漆的贮存稳定性良好,在50℃热加速试验中,贮存1个月无沉淀、无絮凝、无增稠、细度<15μm。所得漆膜的耐溶剂性、凝胶含量、机械性能、耐盐雾性等良好。     

客车涂装底层材料配套性分析

针对南方客户在使用我司客车一段时间后，车身涂层不同程度出现了起泡的质量问题，进行了现场查看，发现起泡位置在车身左右侧蒙皮，且发生在涂层最底层。初步分析原因是热镀锌板+阴极电泳漆 +原子灰三者之间配套存在问题，通过热镀锌板 +阴极电泳漆 +原子灰三者之间的耐高温 80 ℃配套试验，以及室外曝晒试验，得出镀锌板表面是否钝化、电泳漆膜致密程度和原子灰苯乙烯含量是造成涂层底层起泡的主要原因。为了控制涂层起泡问题，重新修订了我司原子灰、镀锌板、电泳漆的技术标准以及部分工艺文件。     

浅析乳胶漆中色浆展色性的影响因素

讨论了乳胶漆中的润湿分散剂、颜填料、乳液、增稠剂、色浆本身等对色浆展色性的影响,以解决体系稳定性,以及颜料絮凝、泛白、浮色发花等弊病,提高色浆展色性。经综合考虑和试验后,得到稳定、高展色性的乳胶漆配方。     

Calcium tripolyphosphate: An anticorrosive pigment for paint

The objective of this work was to evaluate the performance of calcium tripolyphosphate in anticorrosive paints. Its anticorrosive properties were studied in pigment suspensions and in solventborne paints with 10% and 30% of the pigment by volume and a pigment volume concentration/critical pigment volume concentration (PVC/CPVC) equal to 0.8. The behavior of paints formulated with epoxy and alkyd resins was assessed by accelerated (salt spray cabinet and humidity chamber) and electrochemical tests (corrosion potential, ionic resistance, and polarization resistance). Calcium tripolyphosphate was proven to inhibit steel corrosion when incorporated in a paint film. Good protection was achieved employing only 10% by volume of the pigment, instead of 30%, as was suggested in the case of phosphates. The anticorrosion protection afforded by alkyd paints was impaired when the pigment content was increased. Epoxy paints seemed to be less sensitive to the pigment content. Centro de Investigación y Desarrollo en Tecnología de Pinturas (CIC-CONICET), Calle 52 e/121 y 122. (1900) La Plata. Argentina. Fax: 54.221.427. 1537. email: cidepint@ba.net     

Acid rain effects on the exterior durability of architectural coatings on wood

Acid rain is an important consequence of pollutants generated by modern industrial societies and is known to cause damage to ecological systems, construction materials and cultural artifacts. The assessment of the damage caused to paint films has included laboratory, exposure chamber, and exterior weathering experiments. This study uses visual assessment of paints applied directly to southern yellow pine and exposed at 30° south to either natural acid rain or deionized water spray sites in North Carolina and Ohio to determine damage by acid rain. An acrylic latex paint with a pigment volume concentration (PVC) of 52 and a volume solids (VS) of 35% was formulated with calcium carbonate or sodium potassium alumino-silicate extenders. This high PVC paint formulation is one known to stress the binding capacity of the latex and thus produce early grain cracking failures over bare wood. Major effects observed include severe yellowing and increased mildewing of the carbonate containing paints exposed to acid rain. While acid rain can damage exterior paints, much of the damage can be minimized by careful selection of the polymers and pigments used in the formulation.     

Fate of a coalescing aid after latex paint application

Water-based coatings require coalescing aids to achieve properties equivalent to solvent-borne paints. A common coalescing aid in latex paints is 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (TMPD-MIB). The relatively large quantity of TMPD-MIB used in latex paints has raised concerns regarding its emissions to both indoor and outdoor atmospheres. In this study, a one-dimensional dual (paint and material) layer diffusion model was developed to estimate emissions of TMPD-MIB from two latex paints applied to gypsum board. The paints contained different pigment volume concentrations (PVC) and different amounts of TMPD-MIB. Different modeling approaches were used depending on the PVC of the paint. The proposed model for paint drying and TMPD-MIB emissions was tested with data from previous chamber experiments. Experimental data were first used for purposes of parameter estimation, and the model was then compared against an independent experimental dataset. The diffusion coefficient of the paint layer was adjusted as a function of the water content remaining in the wet paint film. The effective diffusion coefficient of TMPD-MIB in the paint layer was found to be dependent on the PVC and water content of the paint.     

不同颜色色浆对氟树脂/铝低红外发射率涂层的影响

研究了大红、深黄、水紫、黑色4种颜色色浆对氟树脂/铝低红外发射率涂层光泽、附着力、硬度、粗糙度、耐冲击性、色差、红外发射率、耐腐蚀性等性能的影响。研究结果显示:深黄色色浆涂层的发射率最低,约为0.1;不同色浆对氟树脂涂层色差明度影响不同,相对于其他色浆,水紫能够使涂层偏暗;大红、深黄、水紫色浆的涂层硬度均为6H;加深黄色浆的涂层附着力最好,其次是大红色浆和水紫色浆;深黄色浆对涂层的耐冲击性影响最大,其次是大红色浆和水紫色浆;相对于大红、深黄、黑色色浆,水紫色浆涂层具有最低的粗糙度,表面比较光滑;水紫色浆和深黄色浆的红外波峰比较持平,有利于减小表面发射率;水紫色浆氟树脂涂层的耐腐蚀性能最好。耐盐水腐蚀测试后4种涂层均没有明显失光,水紫涂层没有发生明显变色,深黄和黑色涂层起泡密度较低。水紫色浆因其粒径均匀细小,在氟树脂涂料中易分散,与氟树脂相容性好,因此具有相对较优的综合性能。     

耐候快干水性木器实色漆的研究及其应用

以水性丙烯酸-聚氨酯分散体为成膜物,以钛白粉为颜料,在润湿分散剂、成膜助剂、消泡剂、增稠剂、纳米SiO2等助剂的配合下,制备了水性木器实色漆。讨论了各原料的选择对涂料性能的影响。     

阳离子改性苯乙烯-马来酸酐共聚物的制备与表征及应用

以2,3-环氧丙基三甲基氯化铵(ETA)为阳离子化试剂,对苯乙烯-马来酸酐共聚物(SMA)进行阳离子化改性,制备出一种阳离子性高分子分散剂(SMG)。通过红外光谱、含氮量、表面张力以及溶解性等的测定,研究了SMG的结构与性质;通过对颜料黄14的分散性考察,研究了SMG的分散性能。结果表明,SMA在阳离子化过程中,酸酐基团全部开环,部分形成酯键,阳离子化度达到7.5%左右;SMG的表面活性较低,但对颜料黄14的分散稳定性较好,在pH=7.0条件下,可以使颜料的Zeta电位提高至 35.4 mV。     

影响眼镜架电泳涂装附着力的因素

介绍了影响金属眼镜架丙烯酸阴极电泳漆涂膜层附着力的多种因素,包括:电泳漆的选择、电导率和pH的控制、电镀层的选择等。并提出一种简单的涂膜附着力检测方法:用普通自来水浸泡,根据设定时间,捞出用指甲剥。作为多品种、少批量流水线作业,此检测方法较简便实用。     

Application of microcalorimetry to the study of interactions in coating formulations

Water-based coating formulations contain many components, such as latex binder, pigment, dispersant, thickener, and surfactant. Complex interactions between these components affect properties of the coating in both the wet and dried states. For example, rheology of the paint is dependent on the interactions of components in the formulation. Pigment interaction can affect the degree of dispersion and, therefore, have ramifications on end use properties such as hiding and tint strength of the paint film. Isothermal titration calorimetry has been used to determine the enthalpy of interaction of the coating components. Representative examples will be given to demonstrate structure–property relationships that correlate the interactions of latex, pigment, surfactant, dispersant, and thickener with paint viscosity as well as end use performance parameters such as adhesion and tint strength.     

Application of silica-containing nano-composite emulsion to wall paint: A new environmentally safe paint of high performance

A new emulsion-type paint was prepared by utilizing a nano-composite emulsion (NCE), which contained nano-size particles (ca. 60 nm in diameter) consisting of silica (inorganic core, ca. 30 nm in diameter) and polyacrylate (organic shell), and evaluated as wall paint. By applying NCE for the wall paint, about 35 wt.% of the organic content in the paint could be reduced in comparison with the commodity emulsion-type paint, which is highly effective to save the petroleum resources. The basic properties of the white NCE paint film on gloss, surface hardness, adhesion, and solvent resistance were evaluated and compared with those of acrylic emulsion-type paints as well as those of silica-containing paints which were prepared simply by blending the acrylic emulsion with silica sol. The NCE paint was especially excellent in solvent resistance. Then the practical tests were performed to evaluate its appropriateness as wall paint, which clarified the excellent antipollution property and the high flame resistance of the NCE paint.