镀锌板上丙烯酸树脂复合膜的制备和表征

在镀锌钢板表面制备了丙烯酸树脂复合膜,用扫描电子显微镜观察膜层的微观形貌.用傅里叶变换红外光谱表征膜层的分子结构,用中性盐雾试验和电化学方法测试其耐蚀性,并用划痕浸泡实验测试膜层的自修复性能.结果表明:丙烯酸树脂复合膜表面致密平整;耐中性盐雾腐蚀达72 h;阻抗值和极化电阻值均较大,说明丙烯酸树脂复合膜能有效抑制腐蚀电化学反应;划痕浸泡试验证明丙烯酸树脂复合膜具有自修复功能.成膜过程中碳酸锆铵能够和丙烯酸树脂分子上的羟基和羧基发生交联反应,形成互穿网络结构,提高膜层内部的交联密度,有效地阻挡外界环境的侵蚀,当膜层破损时钼酸盐和磷酸盐与锌反应形成难溶盐吸附在破损处,起到自修复作用.

Synthesis and Characterization of Complex Acrylate Resin Coating on Galvanized Steel Sheet

A complex acrylate resin coating was synthesised on galvanized steel sheet.The micro-morphology of the coating was observed by SEM.FTIR spectra was used to characterize the molecular structure of the complex acrylate resin coating.The corrosion resistance of the coating was evaluated by neutral salt spray test and electrochemistry test.The self-rehealing performance of the coating was examined with immersion scratch test.The results show that the surface of the coating was uniform and compact.The coating could endure neutral salt spray test for 72 h.And therewith increase the corrosion resistance of galvanized steel sheet with higher impedance and polarization resistance in comparison to the bare galvanized steel sheet.The immersion scratch experiment confirmed that the coating exhibited self-rehealing performance to some extence.The crosslinking reactions may be taken place between ammonium zirconium carbonate(AZC) and hydroxyl and carboxyl of the acrylic resin during synthesis so that to form a high crosslinked density interpenetrating structure network so that the coating could become much effective as a barrier for corrosive substances.When the coating was damaged,there was reaction might take place between zinc with molybdate and phosphate on the surface of zinc to produce water-insoluble salts,which could absorb on the surface of zinc spontaneously to play an important role in coating rehealing.