Electrochemical Behavior of Epoxy Coatings with Nano-sized Pigment
添加纳米锌粉环痒涂层腐蚀电化学行为

The electrochemical behavior of epoxy coatings with different amount of nano-sized zinc pigment has been studied by EIS. The experimental results showed that, nano - sized zinc pigment had remarkably negative effect on the protective performance of coatings. In comprarison with the epoxy resin coating, the corrosion resistance of epoxy resin coatings incorparated with nano-sized zinc pigment was deteriorated. The more the amount of nano-sized zinc added, the worse the corrosion resistance was within a range of 2-20mass% of nano - sized zinc addition. There were two functions of nano - zinc pigment to the epoxy coating. On the one hand, the pigment increased the amount of micro defects in the coatings, which led to the deterioration of the protective property of the coatings, and on the other hand, the corrosion products of zinc filled in the defects in the coatings, which resulted in the improvement of the corrosion performance of the coatings. Within the range of 2 - 20mass% of nano -zinc addition, the former function played more important role than the latter one, resulting in the worse corrosion resistance of the coatings.