水性环氧涂料的制备及其在带锈涂装领域的应用

Preparation and Application of Waterborne Epoxy Anticorrosive Coatings for Rusty Steel Structure

针对工业涂料带锈涂装问题,采用双酚A环氧树脂E44和磷酸反应制备了环氧磷酸酯P-E44,然后经中和、水解等步骤得到了自乳化环氧磷酸酯(HEP),并用傅里叶红外光谱仪对HEP中间体P-E44的结构进行了表征。将0.5%的HEP作为防锈剂添加到双组份水性环氧涂料中制备带锈涂层,采用极化曲线和交流阻抗谱(EIS)2种电化学技术研究了环氧涂层对带锈Q235钢基体在3.5%的Na Cl水溶液中防护性能产生的影响。研究结果表明:HEP能在金属表面形成一层致密螯合物磷化膜,减缓带锈金属进一步发生腐蚀的速率,对金属具有良好的防护作用。

In this paper, a self-emulsified waterborne epoxy phosphate （HEP） was prepared through the reaction of bisphenol A epoxy resin E44 and phosphoric acid followed by further neutralization and hydrolysis, etc. The waterborne epoxy coating was modified by the HEP emulsion with its dosage of 0.5%. The anticorrosive properties of the coating immersed in 3.5% NaC1 solution were investigated by electrochemical impedance spectroscopy （EIS） and polarization curves. The result showed that HEP could form a dense chelated layer on rusty steel surface and inhibit the corrosion, indicating the epoxy phosphate enhanced greatly the corrosion resistance of the epoxy coatings.