THE ROLE OF CATALYSTS IN LOW-GLOSS EPOXY/POLYESTER HYBRID POWDER COATINGS

摘要

In this study, the crucial role played by catalysts in the preparation of low-gloss hybrid powder coatings using a reactive additive (styrene maleic anhydride copolymer) is described. First, the reactions that occur during the cure of epoxy/polyester hybrid thermoset powder coatings are reviewed. DSC measurements on model mixtures and fully formulated powder paints revel relative reactivities and the roles of catalysis on the various reaction steps. The gloss properties of the coatings are found to be closely tied to the presence of a catalyst. Several approaches to preparing powder coating formulations that exhibit fast cure kinetics, low-gloss appearance and excellent properties are described.