Thermoplastic and Thermosetting Powder Coatings Discussed in Detail

A few decades ago, the world of powder coating offered less variety of solid resins that you could use to coat your surfaces. Consequently, service providers had a rather difficult time trying to meet the diverse and ever-changing customer needs. The rising concerns about volatile organic compounds found in regular coating products meant more demand for powder coating. The industry needed a rapid evolution to meet client demands. Technological improvements and better formulations came up, thanks to years of research and product development. Powder coatings are now available in a limitless number of colours, textures and glosses. Here is a discussion on thermoplastic and thermosetting powder coatings for more insight.

Thermoplastic Powder Coatings

Thermoplastic powder coatings melt and flow when they encounter heat. However, they retain their chemical properties and composition upon cooling and solidifying. The coatings are based on high-molecular polymers with unmatched robustness, flexibility and chemical resistance. Usually, the resins included in thermoplastic powder coatings are difficult to grind down to fine particles. These resins also come with a high viscosity and melting point, making them ideal for thick film coating applications. All these elements combined make it hard to apply the thermoplastic coatings via spray application. You are better off using the fluidized bed coating method for the best results. The resulting thick coat is ideal for extreme protective requirements. 

The most popular thermoplastic powder coatings include nylon powders, polypropylene powders, polyvinylchloride powders and polyethylene powders. Notably, the common characteristics of all these powder options are excellent resistance to chemicals, ease of cleaning and a medium gloss for a subtle look. 

Thermosetting Powder Coatings

Thermosetting powder coatings are manufactured using solid resins with a low molecular weight. When you expose them to heat, the thermosetting powders will melt and flow to form a thin, even layer. Chemical cross-linking follows this change as the powders mix within themselves or form new coating compound with other reactive elements around them. In the end, your coating has a different chemical configuration from that of the primary resin used. The newly formed coating is very stable in the face of heat, and it will not soften into a liquid state under heat. Typically, the resins used by manufacturers here are capable of being ground into super-fine particles. This allows a spray application that delivers a thin film coating like ordinary paint.

Manufacturing thermosetting powders involves three primary resins. These are polyester, acrylic and epoxy resins, and they produce five coating options. Epoxy-based coatings are the most popular because they have the best properties for both decorative and functional coating needs.

For more information, contact a powder coating service.