Auxiliaries in powder coatings

/1/ Compatibility of powder coating additives with resins

This is the first attention should be paid to the selection of additives. Powder coating auxiliaries must remain in the powder coating for a long time to play its due effectiveness. Therefore, the general use of additives should be compatible with epoxy, polyester, acrylic and other resins. So usually to compare the compatibility of powder coating additives and resins, the method used is based on the similarity of their structure. For example, the leveling agent is the main additive in the production of powder coatings, can reduce the surface tension of the film, play the role of film homogenization and elimination of shrinkage cavity, so that the cured film to obtain a smooth and shiny surface. When used, supporting agents such as E-12 carrier can not be used in the formulation of pure polyester system, and each company produces a different suitable system for the leveling, which requires powder manufacturers to find the right resin to match, the same is true for brighteners. For example, the B68 type chemical extinction agent containing cycloamidine and polycarbonate that is usually used is only applicable to the system with epoxy. If used in other systems, it will not only lose its due effect, but also have a negative impact on the film.