Study On The UV-Curing Powder Coating

Increasingly stringent health, safety and environmental regulations promote formulators to focus on the development of technologies that meet these regulations. Powder coating, a strict environmentally friendly technology, is gaining double-digit growth. For traditional thermal curing powder coatings, there has a big limit of high curing temperature. They can't coat on heat sensitive substrates such as plastic and wood. How to reduce the powder coatings' curing temperature attracts great interest among researchers. In this aspect, UV curing technology is considered to be the very alternative.In this study, we aimed at developing resins for UV curing powder coatings. To this end, Unsaturated Polyester (UP) and Epoxid Acrylate oligomer (EA) resins was synthesized. For UP resin, the influence of synthesizing process and conditions on molecular weight and glass transform temperature was studied. For EA resin, we studied the relationship between reaction temperature, catalysts, and material proportion and resin property. Two resins which have suitable properties has been developed.The influence of the ratio of two resins, concentration of photoinitiator, and LTV' irradiation time on the properties of cured film was investigated also. The relationship between the coatings corsslinking and performances of coatings film was explored then. The curing process of TGIC modified resin and acrylate end-capped UP resin was tried. It was found that under comfortable curing conditions, the synthesized photosensitive resins have fast enough photo-curing rate. The resulted coating film has high crosslinking degree and acceptable properties.