水性环氧树脂-丙烯酸酯复合乳液制备研究进展

环氧树脂以其优异的性能被广泛应用于各领域,但是由单一环氧树脂制备的水性涂料在性能上无法与溶剂型涂料抗衡。丙烯酸酯乳液具有较好的抗污性、韧性、耐候性等优点,在涂料领域已得到广泛应用。环氧 -丙烯酸酯复合乳液结合了环氧树脂和丙烯酸酯树脂的优点。文章结合国内外水性环氧 -丙烯酸酯乳液的研究现状,重点就水性环氧 -丙烯酸酯乳液制备方法的优缺点进行了分析和总结,并提出了改进思路。提高疏水环氧树脂水性化能力并通过结构设计有望制备稳定和耐腐蚀性好的单组分自交联水性环氧树脂 -丙烯酸酯复合乳液。     

水性环氧-丙烯酸酯复合涂料技术进展

介绍了环氧-丙烯酸酯复合乳液的2种制备方法:自由基接枝共聚和酯化法。综述了水性环氧-丙烯酸酯复合涂料的制备及应用技术进展。     

几种涂料成膜物的最新研究

介绍了玻璃涂料用有机硅羟基丙烯酸乳液、卷材涂料用高固体分聚酯树脂、磷酸酯单体改性水性丙烯酸树脂、羟烷基酰胺(Primid)固化干混消光粉末涂料用户外聚酯树脂、木器涂料用多臂腰果酚基光固化树脂、疏水性SiO2改性含氟硅苯丙复合乳液、木焦油基环氧树脂、水性聚氨酯-丙烯酸酯分散体、反应型非离子水性环氧乳液、阴非离子型水性聚酯树脂等几种涂料成膜物的最新研究,说明了当前存在的问题并对涂料成膜物的研究方向进行了展望。     

水性环氧涂料耐盐雾性影响因素的研究

研究了水性环氧涂料的乳液粒径与PVC(颜料体积浓度)对其耐盐雾性的影响。选择了粒径较小的乳液于适宜的PVC下配制水性环氧涂料,其耐盐雾性与溶剂型环氧涂料相当。通过对比,得出了水性环氧涂料的耐盐雾性不同于溶剂型环氧涂料的影响规律。     

原位聚合法制备石墨烯改性水性环氧-丙烯酸酯乳液及其防腐性能研究

首先采用改进Hummers法制备氧化石墨烯分散液,再用原位聚合法制备石墨烯改性水性环氧-丙烯酸酯复合乳液,并制备其涂层。主要研究了石墨烯改性水性环氧-丙烯酸酯复合乳液的稳定性和复合乳液涂膜的耐腐蚀性。结果表明:石墨烯能够较好地分散在复合乳液中,成膜时能够很好地填充在涂层的细小缝隙中而产生屏障作用,阻碍腐蚀粒子从介质渗透到铁板表面。因此复合乳液的耐腐蚀性较未改性的水性环氧-丙烯酸酯乳液和直接共混乳液的耐腐蚀性明显增强。     

国内期刊荟萃

无溶剂超厚型环氧重防腐涂料的研制,环氧树脂基复合涂层摩擦磨损性能研究,纳米TiO2苯丙复合乳液的制备,薄层隔热涂料的制备及其性能研究     

水性涂料

9902162聚氨酯一丙烯酸酯复合乳液的新进展 1(刊〕/尹朝辉等//涂料工业一1998,28(12)一31一34 较全面地综述了近年来聚氨醋一丙烯酸醋(P UA)复合乳液研究的新进展,重点介绍了几类新型的PUA复合乳液,并对该领域进一步的发展作了展望。图3参“ 通过环氧树脂与聚氨醋的接枝反应,合成了环氧改性聚氨醋乳液,用其配制综合性能良好的水性环氧改性聚氨醋涂料,适用于木地板涂装,使用效果好。讨论了NCO/OH比值、环氧树脂加量和残留异氛酸醋的量对涂料性能的影响。图1表2参3”02163 voc共聚物水胶乳涂料(刊〕/赵劲松//化学建材一1995,(6)一22一24 …     

固化剂对钢结构用超薄膨胀型水性环氧防火涂料性能的影响

以环氧乳液为基料,聚磷酸铵、三聚氰胺、季戊四醇(APP/MEL/PER)为防火助剂研制了超薄膨胀型钢结构防火涂料。通过调整环氧乳液/固化剂比例,研究了固化剂用量对涂料防火、防腐性能的影响。通过交联度测试进一步讨论了环氧乳液与固化剂比例对涂料性能的影响。结果表明:固化剂占环氧乳液含量20%时,涂层的防火性能和防腐性能均较好。     

高阻尼性涂层用环氧-丙烯酸酯复合乳液的合成

采用分步乳液聚合法合成了一种具有核-壳结构的环氧-丙烯酸酯复合乳液,通过核层和壳层之间的化学交联使涂膜具有较高的阻尼性能。通过透射电镜观察到乳胶粒子呈均匀的核-壳球形结构,红外光谱(FTIR)结果表明复合乳液涂膜实现了环氧与丙烯酸树脂的交联反应。动态热机械分析(DMA)显示该乳液涂膜具有较高的损耗因子和较宽的阻尼温域,加热成膜的最大损耗因子(tanδ)达到2.12,明显高于传统阻尼涂料,在tanδ0.3的阻尼温域为40℃,在金属阻尼涂层材料领域具有良好的应用潜能。     

高阻尼性涂层用环氧-丙烯酸酯复合乳液的合成

采用分步乳液聚合法合成了一种具有核-壳结构的环氧-丙烯酸酯复合乳液,通过核层和壳层之间的化学交联使涂膜具有较高的阻尼性能。通过透射电镜观察到乳胶粒子呈均匀的核-壳球形结构,红外光谱（FTIR）结果表明复合乳液涂膜实现了环氧与丙烯酸树脂的交联反应。动态热机械分析（DMA）显示该乳液涂膜具有较高的损耗因子和较宽的阻尼温域,加热成膜的最大损耗因子（tan δ）达到2.12,明显高于传统阻尼涂料,在tan δ >0.3的阻尼温域为40℃,在金属阻尼涂层材料领域具有良好的应用潜能。     

Controlled preparation and properties of acrylic acid epoxy-acrylate composite emulsion for self-crosslinking coatings

A stable epoxy-acrylate composite latex was successfully prepared through emulsion polymerization of modified epoxy acrylic (EPAC) oligomer with acrylate monomer. The EPAC oligomer was obtained using active acrylic acid (AA) to react with epoxy resin. And by regulating the reaction degree of the active hydrogen of AA and epoxide group, there is the acquisition of terminal double bond that gives EPAC reactivity, together with the partial retention of the epoxide group that enables self-crosslinking during film formation. The structural conformation of the oligomer was ascertained by Fourier transform infrared (FTIR) spectroscopy. The factors influencing the stability of the epoxy-acrylate composite latex were investigated. The epoxy-acrylate composite latex was the most stable when methyl acrylic acid was 1.5 wt% and modified EPAC oligomer was 15 wt% of the total monomer weight. The morphology and property of the composite latex films were characterized by scanning electron microscopy, transmission electron microscopy (TEM), and temperature-modulated differential scanning calorimetry (TOPEM-DSC). The results confirm that there is successful emulsion copolymerization between modified EPAC oligomer and acrylate monomer. TEM show that the particles of epoxy-acrylate composite have a core-shell structure, and there is no free epoxy resin. The FTIR and TOPEM-DSC results reveal that the copolymer emulsion possesses self-crosslinking ability. During film formation, self-crosslinking reaction occurs between epoxide groups with carboxyl groups, giving exothermal phenomena. The thermal stability as well as the corrosion resistance of the films was analyzed. The results show outstanding thermal stability as well as corrosion resistance attributable to the crosslinking reticulation structure. It is envisaged that the epoxy-acrylate composite latex has great potential in the development of high-performance aqueous coatings.     

紫外光固化环氧-丙烯酸酯/聚氨酯-丙烯酸酯复合型水性涂料的研制

制备了可反应性的阴离子型聚氨酯-丙烯酸酯，并用其作为乳化剂制成了可紫外光固化的水性环氧-丙烯酸酯／聚氨酯-丙烯酸酯复合型水性涂料。讨论了聚氨酯-丙烯酸酯的乳化机理，及其对环氧-丙烯酸酯水分散体系稳定性及涂膜性能的影响。     

UV固化涂料研究进展

综述了UV固化涂料组成与固化机理。详细介绍了国内外不饱和聚酯、环氧丙烯酸酯、聚氨酯丙烯酸酯、水性UV固化聚氨酯丙烯酸酯的研究进展。结合对其深入研究及新产品的不断开发,UV固化涂料将向传统涂料的各个应用领域迅速扩展。预计未来将会出现更多的UV固化水性涂料和UV固化粉末涂料。     

Correlation of hardness with MFFT and CPVC of latex/ceramic coatings

Hardness, porosity, and microstructure of film-forming in polyvinyl acetate/alumina coatings from aqueous suspensions were investigated with a minimum film formation temperature (MFFT) bar, Vickers hardness tester, and scanning electron microscopy (SEM). The hardness of opaque composite coatings (alumina:latex=1:2 by volume) increased abruptly at the MFFT of the latex, suggesting that the alumina particles did not change the latex film formation behavior and that the hardness measurement is an alterative to the optical criterion. Studies of coatings from latex particles that were smaller or larger than a common size of ceramic particles indicated that the composition of maximum hardness, called critical Vickers hardness concentration (CVHC), matched conventional critical pigment volume concentration (CPVC). More efficient polymer binding in the coatings from the smaller latex gave them higher peak hardness and CPVC. Department of Chemical Engineering & Materials Science, 421 Washington Ave., SE, Minneapolis, MN 55455-0132.     

Heterocoagulation as an Inclusion Coating Technique for Ceramic Composite Processing

Colloidal heterocoagulation in aqueous media was used to form coatings of alumina or polystyrene latex particles on alumina spheres and of alumina or latex particles on silicon carbide whiskers. The polyelectrolyte dispersants poly-(ammonium methacrylate) and poly(ethylenimine) were used to alter the inherent surface potentials of the materials to increase the applicability of this technique. In most cases, the coatings formed were partial monolayers, although thicker coatings of alumina were formed on the SiC due to aggregation of the alumina. The oxide coatings were relatively well adhered while the latex coatings were easily removed in aqueous media. The adherence of the latex coatings was improved by adding low alcohols to the heterocoagulating suspension.     

Fabrication of an epoxy graft poly(St-acrylate) composite latex and its functional properties as a steel coating

A novel method for preparing epoxy graft poly(St-acrylate) composite latex with high graft ratio has been devised. First, esterification was carried out between acrylic acid and an epoxy resin using the monomer as the solvent. The obtained sample, still in solution in the monomer, was emulsified to miniemulsion droplets together with other monomers. Finally, the epoxy graft acrylate composite latex was prepared by miniemulsion copolymerization. This technology will eliminate pollution arising from the organic solvent when solvent-borne systems are used. The enhanced graft ratio was confirmed by FTIR and ¹H NMR measurements. The results indicated that the acrylic monomer was grafted onto the epoxy chain. TEM showed the graft composite latex to have a spherical structure with diameter 100 nm. The adhesive performance and anti-corrosive properties on a steel substrate, as measured by salt-spray resistance, were maximized when 4.0% acrylic acid was added to the epoxy resin. Dynamic mechanical analysis (DMA) has been employed to test the damping properties of the composite latex coatings. It was interesting that the tan δ peak values of the coatings were as high as 2.15, clearly exceeding those of general damping materials. Our findings suggest great potential for the composite latex in the field of functional steel coatings.     

Effect of particle size distribution on stress development and microstructure of particulate coatings

The role of pigment particle size distribution on stress and microstructure development was studied for coatings prepared from aqueous suspensions of ground calcium carbonate (GCC) and latex binder. Stress development was monitored using a modified beam deflection technique under controlled environment. Microstructure was characterized by scanning electron microscopy (SEM) and cryogenic SEM. For coatings containing only GCC particles and no latex, a wide particle size distribution resulted in a significant particle size gradient in the cross-sectional microstructure and irregular stress development. With latex addition, uniform microstructures were observed in coatings with either wide or narrow GCC particle size distribution. GCC/latex coatings prepared using GCC with a wide particle size distribution developed a higher stress than those prepared using GCC with a similar average particle size but a narrow particle size distribution. The higher stress is related to the particle packing that results in smaller pore sizes and larger capillary pressures that drive compaction. In coatings prepared with the same GCC particles but different latex binders, the stress and cracking behavior of the coating depends on the latex properties.     

Growth mechanism and pH-regulation characteristics of composite latex particles prepared from Pickering emulsion polymerization of aniline/ZnO using different hydrophilicities of oil phases

A Pickering emulsion polymerization of aniline, using different hydrophilicities of oil phases, was stabilized by ZnO nanoparticles and performed to synthesize composite latex particles of polyaniline/ZnO. Ammonium peroxydisulfate (APS) was used as an oxidizing agent. The morphologies and growth mechanisms of the resulted composite latex particles were studied. The pH-regulation capacity of the composite latex particles was discussed. When toluene was used as the oil phase, the composite latex particles showed hollow structure, irregular morphology, and hundreds of nanometer in size. It was ascribed to the polymerization of aniline on the interfaces of droplets/water. ZnO nanoparticles, with 50-100 nm in size, acted as surfactants to stabilize the emulsion. When THF was used as an oil phase, the composite latex particles showed spherical morphology and enwrapping ZnO nanoparticles. It was attributed to the homogeneous nucleation of polyaniline in the aqueous phase. ZnO nanoparticles acted as templates for the polyaniline particles. The stability of the Pickering emulsion polymerization was affected by the volume ratio of the oil phase to water. The aqueous solution with pH 3-9 could simply be regulated to about pH 7 by the composite latex particles. It was contributed by the dissolution of ZnO nanoparticles and doping-dedoping of polyaniline in the acidic and alkaline aqueous solutions.     

薄型隧道专用防火涂料的研制与应用

通过对当前隧道防火涂料所用原料的分析,针对隧道用防火涂料的要求,以水泥和乳胶粉为复合黏结剂,以多种复合材料为隔热填料,在多种助剂的配合下,研制出薄型隧道专用防火涂料。该涂料耐火极限高,粘结强度大,环保无毒,各项技术指标都超过了国家隧道防火涂标准要求,市场前景广阔。