Preparation And Characterization Of Waterborne Polyester Insulation Paint

With the increasing of environment awareness of human-beings and improving of coatings industry’s environmental standards,coatings with low VOC content which has less or no organic solvents became to an inevitable development trend.For the source of raw materials was rich,the range of applications was wide,the costs were appropriate,waterborne coatings had the most potential to replace traditional solvent-based coatings in multiple fields of application.The application of it in electric equipment as insulation paint remained to be expanded.Waterborne polyester insulation paint was a kind of coating with excellent insulating properties,hardness,surface gloss and good weather resistance.It was suitable for using as insulation paints.Researchers did some work on the waterborne polyester paint however work of using5-sodiumsulfoisophthalate(5-SSIPA)as aqueous monomer to prepared waterborne polyester paint and studies of its performance was still relatively rare.In this paper we used phthalic anhydride,adipic acid,neopentyl glycol,trimethylol propane and 5-SSIPA to prepare a series of waterborne polyester contained different mount of 5-SSIPA.Waterborne polyester insulation paint and the film had been prepared by these polyesters.The influence on water-soluble of polyester by different ways of polymerization and amount of 5-SSIPA had been studied through FTIR and water-soluble test.The effect on polymerization by alkyd ratio,pumpdown time had been explored by GPC,acid value and hydroxyl value.Mechanical properties,heat resistance and electrical insulation of paint film were characterized.Regularity between amount of curing agent,5-SSIPA and performance of paint had been discussed.It turned out two-step method is conductive to make sure 5-SSIPA react completely.Polyester exhibited good water solubility when the amount of 5-SSIPA was more than 10%.The reaction was completed quickly and efficiently if the alkyd ratio came to 1.34:1 and the vacuumized time was 100 min.When the amount of curing agent meet 70% of polyesterweight,the mechanical properties of film was best.With the amount of5-SSIPA increasing,the viscosity of the paint increased,storage stability reduced.However,with the paint amount increased,the gelation time reduced.It also showed significant adverse effects to insulation properties of the paint.Considering water solubility,constructability,mechanical properties and electrical insulation,the amount of 5-SSIPA meet 10% amount of substance of dicarboxylic acid made the paint have low VOC and high solid content.Also its performance meet the application requirements of insulation paint.