| Various resins of acrylate-modified polyesters, used for UV curable powder coatings, were synthesized. The process and recipe of resin preparation were studied. And UV-curable powder coatings systems were formulated with regard to resin blending. The effects of powder coating formulations on properties of cured film such as adhesive attraction, resistance to impact, resistance to organic solvents, pencil hardness, gloss were further studied.Some systemic research was conducted on photosensitivity of the polyester, discussing the factors affecting photo-curing processes such as the type of the photoinitiators, the amount of the photoinitiators, as well as temperature and time of IR leveling. UV power, Irradiation time, Irradition distance, film thickness was measured to get to the high performance. It was also shown that the introduction of semi-crystalline unsaturated polyester improves the properties such as resistance to direct and reverse impact, adhesive attraction of the cured films.The dependence of rheology of UV-curable powder coating on resin ratios of amorphous and semi-crystalline polyester and filler levels was investigated. The leveling was found to be dependent on the viscosity of the coating. To reach a good leveling, it is necessary for temperature to be over the melting temperature of the semi-crystalline resin.Technics of UV curable powder coating involves UV power, UV curing time, lighting distance, film thickness etc. These factor have a important role on coating performance.
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