Preparation method:
(1) Preparation of acrylic prepolymer. Add part of the diluent into the flask, pass N, heat up to the reflux state, add monomer and part of diisopropylbenzene peroxide, drop for 3h, and keep warm for 1h; Then add the remaining diisopropylbenzene peroxide and diluent, drop for 15min, hold for 3h; Cool down, discharge.
(2) Preparation of polyester acrylic resin. 27% of the total amount of acrylic prepolymer, trimethylol propane, neopentyl glycol and adipic acid were added to a four-way flask, heated by N, and kept warm for 1h at the reflux temperature of 140 ~ 180℃. Use 0.5h to increase the temperature to 220~230℃, heat preservation esterification. After 2h, the temperature drops below 140℃, and the acid value is measured. If the acid value is less than 20mgKOH/ g, the remaining acrylic prepolymer is added. If the acid value is >20mgKOH/ g, continue esterification until the acid value is ≤20mgKOH/g before adding the remaining acrylic prepolymer. After adding, the temperature is raised to about 220℃, the heat is kept until the acid value is less than 15mgKOH/g, and then the temperature is lowered and the diluent is added.
(3) Preparation of polyester acrylic resin thermochromic paint. The polyester acrylic resin was diluted with xylene solution to the viscosity of about 40s, and the heat discolouring material was added under agitation, and the heat was held at 40 ~50℃ for 5min, and then the additives and fillers were added, fully stirred, and the finished product was sanded.
Properties
Polyester acrylic resin with excellent properties as the main film forming material, the inorganic thermal discoloration material dispersed in polyester acrylic resin, polyester acrylic thermal discoloration coating made of excellent performance, heat discoloration effect is obvious. Table 8-58 describes the coating properties.
Application
This product is widely used in decoration, automobile, chemical anti-counterfeiting and various industrial fields.