Material selection for high temperature powder coating formulations

China Coatings Online News Information: High temperature-resistant powder coatings are mainly composed of high-temperature resins, high-temperature pigments, high-temperature fillers and special effects additives, and are widely used in chemical, petroleum, metallurgy, aviation and other industries because of their outstanding high temperature resistance. At present, heat-resistant powder coatings are still dominated by silicone powder coatings. The selection and control of each group in silicone powder coating is the basis for high temperature-resistant silicone powder coating.
1, the use of silicone resin in high temperature-resistant powder coating
silicone resin with silicone oxygen bond as the main chain, because of its high bond energy and give silicone resin high oxidation stability, and can create a stable protective layer on the coating surface. And the use of silicone resin alone, its molecular force is small, poor adhesion, high price, in the premise of meeting the relevant properties, generally add a moderate silicone resin in the resin to solve the above problems.
the increase of silicone resin in a certain range, the longer the service life and heat resistance time of the coating film. It is mentioned in the literature that when the addition of a silicone resin increases from 0.1 to 0.3, the heat resistance time of the coating film increases from about 50h to 100h.
of course different silicone resins to be determined by experiments.
2, pigment selection
because inorganic pigments than organic pigment heat resistance is superior, so high temperature powder coatings generally do not consider organic pigments>, mainly from inorganic pigments to choose suitable and stable performance> After the barbecue mica powder is the best, the rest is few.
In addition, the amount of pigment is also affected by temperature resistance, and the optimal dosing range of 60%-100% (compared to resin problems) is determined in the Application of Silicone Resin Heat-resistant Powder Coatings.
3, the choice of additives
the selection of suitable additives, but also to improve the high temperature-resistant powder coating film resistance to high temperature and mechanical properties of an important part. Such as the addition of antioxidants, hardeners, etc. to high temperature-resistant powders.