Novel ambient temperature curable two-component waterborne silicone-acrylic coatings

Waterborne coatings are composed of resins containing hydrophilic functional groups. These groups usually remain in the coating film and can adversely affect film properties such as weatherability and resistance to water and alkali. We have developed a novel ambient temperature curable waterborne two-component system, in which the hydrophilic functional groups are consumed by the crosslinking reaction. The new coating system consists of a waterborne acrylic resin containing both tert-amino and carboxylic acid groups and a hardener containing both epoxy and alkoxysilyl groups. The waterborne silicone acrylic coatings provide superior film properties even if the acrylic resin has relatively low functional group content. In this paper we describe the crosslinking reaction mechanism and film properties using some acrylic resin types and paint formulations as examples. Presented at the 24th Annual Waterborne, High-Solids, and Powder Coatings Symposium, on February 5–7, 1997, in New Orleans, LA. 1-3 Takasago, Takaishi-shi, Osaka, Japan.     

底面合一阴极电泳漆的研究

采用丙烯酸树脂与环氧树脂冷拼工艺制备的阴极电泳漆解决了环氧类阴极电泳漆作为底面合一涂层时老化性能差的问题，针对乳液在施工应用中的稳定性，探讨了亲水性溶剂、酸值对乳液及电泳漆漆膜的影响，通过液相色谱仪分析槽液中树脂比例变化，并用人工加速老化实验验证了涂膜的老化水平，结果表明，底面合一型电泳漆在老化、盐雾等方面达到了和谐统一，可满足有关汽车底盘及零部件的综合要求。     

阴极电沉积环氧涂层表面形态的扫描电子显微镜研究

以环氧型中厚膜阴极电泳涂料为模型，用扫描电子显微镜考察了不同电泳涂装参数及烘烤固化条件对电泳漆膜表观形态的影响。试验结果表明：通过调节电泳电压和电泳时间，可以控制膜厚。对于在不同电压和电沉积时间得到的相同膜厚的电沉积膜，较低的电压、较高的固化温度和较短的固化时间均有利于获得平整、光滑、致密的涂层。     

PET金银镀铝膜专用烘烤漆的配方设计

从金银线专用烘漆的工艺和性能要求出发,探讨了聚酯真空镀铝膜(VMPET)烘漆的配方设计的要素,实验优选出氨基烘漆体系,研究表明氨基树脂和成膜树脂是获得高性能烘漆的重要因素,通过优选氨基烘漆配方各组分,可获得具有较高应用性能的金银线专用烘漆。     

Preparation of waterborne phosphated acrylate–epoxy hybrid dispersions and their application as coil coating primer

In this paper, a series of waterborne acrylic-modified epoxy hybrid dispersions were synthesized and successfully used as primers for coil coatings. Epoxy was phosphated to improve its adhesion to the metal substrate. The grafting reaction of acrylate monomers onto the high molecular weight epoxy resins was studied with infrared spectroscopy, differential scanning calorimetry, and nuclear magnetic resonance. The structure and resin molecules were found to be as expected and the film had the best performance when the acrylate monomer made up less than 40 wt% of the epoxy resin. Modification of the epoxy with phosphoric acid could increase the adhesion to the metal substrate. Better adhesion was achieved with greater amounts of phosphoric acid. R578 urea resin was found to be the most suitable for crosslinking of the resin in this system, and a paint film based on the resulting resin had excellent overall performance.     

环氧树脂基双组分水性聚氨酯的制备及其在木器涂料中的应用

为提高双组分水性聚氨酯的室温交联速度,将N-苄基乙醇胺引入到环氧树脂制备了环氧树脂基水性多元醇,表征了多元醇的化学结构,并测定了其相对分子质量、粒径分布和玻璃化温度等主要技术参数。将环氧树脂基水性多元醇与多异氰酸酯配合制备了双组分水性聚氨酯,采用红外光谱法研究了室温交联反应过程。研究结果表明:多元醇分子结构中引入苄胺基加快了双组分水性聚氨酯的交联反应速度。将双组分水性聚氨酯制备成水性木器涂料,漆膜具有优异的耐冲击性、附着力、柔韧性、光泽、耐液体介质、硬度、丰满度等性能。     

阴极电沉积涂料的无铅化研究

将铋离子应用于环氧体系阴极电沉积涂料中，从槽液参数、漆膜性能等方面分析了铋离子代替铅离子作为阴极电沉积涂料催化剂的优势，证明了铋离子应用于阴极电沉积涂料的可行性。     

光固化涂料用低粘度环氧丙烯酸酯的研究

采用双羟基化合物与环氧树脂进行反应,制取低粘度改性环氧树脂,然后用丙烯酸酯化,制得光固化涂料用低粘度环氧丙烯酸酯。研究了催化剂类型和用量对环氧树脂改性反应,以及不同结构、不同链长双羟基化合物和双羟基化合物与环氧树脂当量比对环氧丙烯酸酯粘度及其配制的光固化涂料的性能影响。确定了环氧树脂改性反应和丙烯酸酯化反应的最佳条件。     

低温固化环氧阴极电泳涂料的大分子交联剂的制备

首先以聚乙二醇200(PEG-200)、异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)为原料合成了末端为异氰酸根(—NCO)的预聚体,再以N-甲基二乙醇胺(MDEA)为封端剂对—NCO进行全封端反应。通过添加适量的亲水性DMPA,提高了封端大分子的自乳化性能,制备出全封闭型异氰酸酯大分子(P-M-I)乳液,以其作为环氧阴极电泳漆低温固化的交联剂。应用FT-IR、DSC、TG、TEM、粒径分析等检测手段对全封闭型大分子及其乳液进行了结构与性能表征。将其与胺化环氧树脂乳液进行共混,制备了低温固化环氧阴极电泳涂料。通过电泳涂装的金属样片在124～130℃烘烤30 min可完全固化成膜。实验结果表明:该大分子交联剂显著降低了电泳涂料的固化温度,涂膜外观平整光亮、附着力好、铅笔硬度达2H,综合性能良好。     

丙烯酸阴极电泳漆的研制

介绍了采用甲基丙烯酸缩水甘油酯与常用的丙烯酸单体通过溶液聚合,制备丙烯酸阴极电泳漆的简单可行方法。研制的电泳漆克服了环氧-聚氨酯阴极电泳漆的缺点,具有可着色性、高装饰性、高耐候性等特点。讨论了影响电泳漆性能的诸种因素。列举了电泳原漆的技术指标、施工参数和漆膜性能指标。     

UV固化水性环氧树脂的改性研究

用顺丁烯二酸酐对双酚A型环氧树脂(E-51)进行化学改性引入亲水性基团和不饱和基团，成盐后制得UV固化水性环氧树脂体系。确定了最佳的原料配比、反应温度和时间，并利用红外光谱对产物的结构进行了表征。结果表明：该改性E-51环氧树脂可与水以不同的配比形成水溶液或水乳液，体系具有优良的稳定性；该体系可用紫外光固化。     

低电子阻抗环氧树脂的合成

采用金属钙络合离子中间体与双酚A型环氧树脂合成了低电子阻抗的环氧树脂,通过多元胺固化剂交联制备了低电子阻抗的环氧树脂固化物。用差示扫描量热法和热重分析法分别测试了低电子阻抗环氧树脂的固化过程与固化产物的热稳定性,考察了金属钙络合离子中间体与环氧树脂的用量比及反应时间对固化物的体积电阻率的影响。结果表明,引入金属钙络合离子中间体后,环氧树脂E-51固化物的冲击强度为12.1kJ/m2,弯曲强度为78.9MPa。     

HB-2000环氧树脂厚膜阴极电泳漆的施工应用

介绍了HB-2000环氧树脂厚膜阴极电泳漆的应用情况,讨论了阴极电泳涂装工艺以及施工中的注意事项.     

低温阴极电泳漆的制备及性能

随着人们对环境保护以及低能量消耗要求的不断提高,低温固化阴极电泳漆已经成为电泳漆的发展趋势之一。合成了封闭物异氰酸酯固化交联剂,并探讨了反应时间和反应温度对封闭率的影响,最后以氨化改性环氧树脂为基料树脂合成了低温固化阴极电泳漆。实验结果表明：在150℃／20min的固化条件下,漆膜能得到完全固化,经过漆膜综合性能实验,在选择合适的电泳工艺参数下,可以得到硬度较高、耐潮、耐盐、耐酸碱性能好的漆膜。     

拉链头用高耐水洗水性烘烤漆的研制

针对溶剂型烤漆对环境和人体带来危害、水性烘烤漆水洗易掉漆的问题,采用水性环氧树脂为成膜基料,通过对氨基树脂固化剂以及功能助剂的筛选和配方设计,研制出一款拉链头用高耐水洗水性烘烤漆,并且确定了最佳烘烤温度。实验结果表明：当以氨基树脂 Cymel MM-100为固化剂,水性环氧树脂和固化剂的质量比为 10∶1,水性环氧基聚硅氧烷 Um-623的添加量为 3%,烘烤温度为 150 ℃,得到的漆膜附着力 0级,耐冲击性 50 cm,铅笔硬度 2H,耐磨性 <0. 03 g,漆膜耐水洗色牢度性能优异。     

水溶性醇酸氨基烘漆的研制

采用饱和脂肪酸、苯酐、三羟甲基丙烷、新戊二醇和偏苯三酸酐合成水溶性醇酸树脂,与甲醚化三聚氰胺甲醛树脂制备水溶性醇酸氨基烘漆。该水溶性醇酸氨基烘漆的漆膜性能均达到并超过溶剂型醇酸氨基烘漆的漆膜性能。讨论了酸值、羟值、油度、氨基树脂、中和剂、助溶剂和树脂结构等因素对树脂合成及应用性能的影响。水溶性醇酸氨基烘漆与水性醇酸防锈底漆配套使用具有优异的防腐性能。     

简述OEM汽车涂料的新进展

介绍了OEM汽车涂料的组成及复合涂层体系,全球五大涂料生产商所占汽车涂料市场份额概况以及CED涂料、高固体分涂料、水性涂料、粉末涂料等主要汽车涂料的技术进展情况,并指明了汽车涂料未来发展的方向与挑战。     

Development and characterization of silicone/phosphorus modified epoxy materials and their application as anticorrosion and antifouling coatings

Epoxy resin is chosen for our present study owing to its exceptional combination of properties such as easy processing, high safety, excellent solvent and chemical resistance, toughness, low shrinkage on cure, good electrical, mechanical and corrosion resistance with excellent adhesion to many substrates. This versatility in formulation made epoxy resins widely applied for surface coatings, adhesives, laminates, composites, potting, painting materials, encapsulant for semiconductor and insulating material for electric devices. There are numerous paint/coating systems based on epoxy resin available for corrosion and fouling prevention. They however are not completely satisfactory in field applications, where high corrosion, fouling and flame resistance are required. The demand for epoxy resin as corrosion/fouling resistant coatings is restricted mainly due to its inferior characteristics like poor impact strength, high rigidity, and moisture absorbing nature besides inadequate flame retardant properties. It is for this reason that silicones and phosphorus-based compounds are used as modifier in this work by intercrosslinking network mechanism (ICN) to obtain epoxy resin with desired properties ideally suitable for field applications for preventing corrosion and fouling with flame retardantancy. The present work involves the development of solvent free silicone/phosphorus modified epoxy coating systems, since solvent free coating systems are widely used for numerous applications due to their lower cost per unit film thickness, freedom from fire and pollution hazard and ability to provide better performance. For the development of coating systems, epoxy resin (X) serves as base material, hydroxyl terminated polydimethylsiloxane (HTPDMS) as modifier, γ-aminopropyltriethoxysilane (γ-APS) as crosslinking agent and dibutyltindilaurate (DBTDL) as catalyst. Polyamidoamine (A), aromatic amine adducts (B) and phosphorus-containing diamine (C) were used as curing agents. The study also describes the evaluation of corrosion resistant behaviour of unmodified epoxy and siliconized epoxy coatings by potentiodynamic polarization method, electrochemical impedance spectroscopy (EIS), salt-spray and antifouling tests. The results are discussed.     

Computer simulation of structure and properties of crosslinked polymers: application to epoxy resins

In this work, a methodology has been developed for construction of atomistic models of crosslinked polymer networks. The methodology has been applied to low molecular weight water soluble epoxy resins crosslinked with different curing agents that are being considered for use as a primer coating on steel. The simulations allowed the crosslink density and the amount of free crosslinking sites in the coatings to be predicted. Shrinkage of the resin upon curing was reproduced by the simulation. In addition, the barrier properties of the model coatings were estimated. The interface between an inorganic substrate and cured epoxy resin has been constructed and the strength and molecular mechanisms of adhesion have been revealed. The developed methodology has a potential to significantly impact on the design and development of new coatings with improved barrier and adhesion properties.     

Novel crosslinking system with hydroxyl-containing polymer, alicyclic polyepoxide and polyalkoxysilane

The crosslinking system based on the reaction among alicyclic epoxide group, hydroxyl group and alkoxysilyl group in the presence of aluminum β-diketone chelate have been developed. Five kinds of reaction are possible, and the result of gas chromatography and infrared analyses indicated that the main reaction is the ring-opening reaction of alicyclic epoxide group with hydroxyl group and/or hydroxysilyl group. The acrylic resin obtained by free radical polymerization of these three kinds of functional monomers and non-functional monomers showed good curing property, and the film was superior in acid rain resistance and outdoor durability. The resin is suitable to use in automotive 2coat–1bake clear coat. The viscosity of this binder system was remarkably reduced by addition of a low molecular weight alicyclic polyepoxide compound and an alkoxysilane oligomer without affecting to its good curing property. Such a system made it possible to design novel high solid coatings. It was found that the crosslinking could be extended to the combination of a polyester polyol, an alicyclic epoxide compound and an alkoxysilane oligomer. In this case, it was necessary that the polyester polyol contained highly reactive terminal hydroxyl group in the branch chains.