With rapid industry development, environmental protection issues are being taken more and more seriously all around the world, especially in China. In early 2015, the Chinese government claimed that solventborne coatings manufacturers began to pay a VOC tax as high as 4%. Because powder coatings are almost free of VOCs, this will provide powder coatings manufacturers more development opportunities and support from local government.
Powder coatings are widely used in various fields, such as architecture, automobiles, pipelines, IT mobile and telecoms, and domestic appliances. For powder coatings, the fight against corrosion has not been stopped. Although the oil and pipeline industry has developed a reliable cathodic protection method, they also experience coating failures. The main reason for this lies in a number of factors.1 The coating system includes binders, pigments and extenders, additives, the type of substrate, pretreatment, curing, coating thickness, adhesion, and the external environment, such as the temperature, moisture, bacteria and UV. All the corrosive relationships are displayed in Figure 1.