Powder coatings are a rapidly growing segment in the coatings market usually associated with the coating of metals. These coatings are growing at 7.6% annually and are expected to reach $12.48 billion by 2020.1 Developed in the late 20th century as a more environmentally friendly option, today powder coatings can be found in a huge span of applications. Whether it’s a child’s first bicycle in powder-coated pink or a colossal pipeline channeling oil across vast distances, the coating protects against repeated mechanical stresses, weather and other environmental challenges that will be faced in the end-use application. Without the proper protective coating, the formation of cracks, chips, blisters, delamination, rust and corrosion damage caused by the environment can ultimately lead to failure.
Powder coatings are favored in many protective coating applications for their superior ability to defend against these threats. However, there are many formulation considerations to achieve the optimal balance of properties for a particular end use and preventing coating failure. To create a powder coating, the formulator combines dry polymer resin systems, curatives, flow control agents, pigments and various other additives, which are then ground into a very fine, uniform powder. This powder is then deposited on the substrate by either dipping the substrate into a fluidized bed of powder or by electrostatically charging the powder and then spraying it onto the substrate, after which time the part is placed in an oven for curing. Of the two major types of powder coatings, thermosets and thermoplastics, thermosets dominate the powder coating market due to their outstanding performance properties and wide formulation options.