Polyester resin for powder coating as well as preparation method and application of polyester resin

The invention provides polyester resin for a powder coating as well as a preparation method and application of the polyester resin. The polyester resin for the powder coating is prepared from the following raw materials: diamine, maleic anhydride, (methyl) acrylate monomers, dihydric alcohol and/or polyhydric alcohol, dibasic acid and/or polybasic acid and an acidolysis agent. According to the invention, the polyester resin is modified by adopting a bismaleimide structure and an acrylic resin structure, so that the synthesized polyester resin has higher glass transition temperature and proper viscosity, a cured coating has excellent leveling performance, the storage stability of the powder coating is better, and the powder coating has good weather resistance. And meanwhile, the powder coating has certain weather resistance and heat resistance. 本发明提供一种粉末涂料用聚酯树脂及其制备方法和应用，所述粉末涂料用聚酯树脂包括以下制备原料：二元胺、马来酸酐、(甲基)丙烯酸酯类单体、二元醇和/或多元醇、二元酸和/或多元酸和酸解剂。本发明采用双马来酰亚胺结构和丙烯酸树脂结构来改性聚酯树脂，使合成的聚酯树脂具有较高的玻璃化转变温度和合适的粘度，固化后的涂层具有优异的流平性能，粉末涂料的