Difference between thermosetting powder coatings and thermoplastic powder coatings?

Thermosetting refers to the heating can be cured cross-linked, cross-linked coating is insoluble, there are chemical reactions in the heating process. Thermoplasticity refers to the powder can be softened after heating, but not cross-linked, only physical changes in the heating process without chemical reaction. The specific performance differences are as follows.

Thermoplastic powder coatings. Thermoplastic powder coatings began to appear in 1950. It melts at spraying temperature and solidifies into films when cooled. Because of the simplicity of the processing and spraying methods, powder coatings need only be melted, leveled, cooled or solidified into films by heating, or solidified by extraction, without complicated solidification devices. Most of the raw materials used are common polymers on the market, which can meet the performance requirements under most conditions. But there are also some shortcomings, such as high melting temperature, low coloring level, poor adhesion with metal surface and so on. Nevertheless, the commonly used thermoplastic powder coatings still show some unique properties, among which polyolefin powder coatings have excellent solvent resistance; polyvinylidene fluoride coatings have outstanding weatherability; polyamide has excellent wear resistance; polyvinyl chloride has a good price / performance ratio; thermoplastic polyester powder coatings have an appearance. Beautiful, artistic advantages. These characteristics make thermoplastic powder coatings occupy a large proportion in the coatings market.

Thermosetting powder coating is a kind of hard and insoluble coating which takes thermosetting resin as film forming material and adds curing agent to form cross-linking reaction after heating. If the temperature is higher, the coating will not soften like thermoplastic coating, but only decompose. Because the resin used in thermosetting powder coatings is prepolymer with lower polymerization degree and lower molecular weight, the coating has better leveling and decorative properties, and the low molecular weight prepolymer can form a network of crosslinked macromolecules after curing, so the coating has better corrosion resistance and mechanical properties. Thermosetting powder coatings are developing rapidly.