Preparation of An Anti-shrinkage Powder Coating on Contaminated Workpieces
The anti-shrinkage powder coating was prepared by using epoxy and polyester as the main film-forming materials,adding defoaming agent,anti-pollution additive and surface conditioning agent,controling the particle size of powder coating products.The influence of the gelation time of polyester resin,the amount of defoamer,anti-pollution additive and surface modifier,and the particle size of the product on the shrinkage of the workpiece during the construction of powder coating were discussed.The results show that the powder coating prepared by using saturated polyester with gelling time of 130 seconds as film-forming material,adding 1%defoamer,0.3%anti-fouling additive and 1%surface modifier,and controlling the particle size D50 of the product at 35 μm has good anti-shrinkage effect in the case of dense defects,resid ual water,oil,treatment solution and residual protective layer of the substrate.