| abstract |
A polyester resin and preparation method therefor, and a coating and a workpiece comprising same. The polyester resin has an acid value of 48-55 mg KOH/g, a glass transition temperature of 68-75°C, a softening point of 110-115°C, and a melt viscosity at 200°C of 7,000-10,000 Pa·s. The polyester resin is prepared from the following raw material components by mass fraction: 20-35% of aliphatic diol, 5-25% of heteroaromatic diol, 45-60% of an aromatic dicarboxylic acid, 5-10% of a capping agent, 0.6-1.5‰ of an esterification catalyst, and 0.5-3% of an aid. By means of the method, the polyester resin is suitable for a TGIC curing powder coating; and a cured coating layer has excellent heat resistance and frost resistance performance, and thus can solve the problems of insufficient heat resistance performance and easy frosting of a polyester powder coating. |