Design And Research On Epoxy Interior Coatings For Container

The first part is the improvement of the solvent-based epoxy interior coating for container. To improve the coating’s adhesion after600h salt spray, the experiment was designed. Effects of ratio of high molecular weight epoxy resin, dosage of phosphate zinc which was an anti-rust pigment, new kinds of curing agent were discussed in detail. The results show that:when the mass ratio of epoxy resin A(K165) to B (Y138)was8:2, the dosage of phosphate zinc was5%,the dosage of E(AM2654) which was added to the curing agent was5%, the coating’s adhesion after salt spray was improved significantly.the hatch adhesion was from level3to level l;the drawing adhesion was from3.5MPa to4.5MPa;the fineness was50μm; the surface drying time was15min;the semi-hard drying time was12h;the pot life was5h,the impact resistance was50kg·cm; the flexibility was2mm;the anti-sagging was1250mmand each performance could meet the requirements.The improved formulation’s cost was a little higher than the original one’s, but from a long-term point of view it was valuable.The second part is the design of the high solid solvent-based epoxy interior coating for container, which was according to the environment requirements. Effects of ratio of different molecular weight epoxy resin, different reactive thinner, new kinds of curing agent and different anti-settling system were discussed in detail. The results show that:when the mass ratio of epoxy resin B (Y127)was30%～40%in total, the dosage of active thinnerM(C513) was10%, E(S390) was added to the curing agent, and the organic modified bentonite R was chosen as the anti-settling system (the adding amount was1%of the total formula),the coating had the bestanti-corrosive performance.The anti-acid time was250h;the anti-alkali time was300h;the salt spray resistance was1050h; the fineness was60μm; the surface drying time was30min;the semi-hard drying time was16h;the pot life was5h;the hatch adhesion was level1;the impact resistance was50kg·cm; the flexibility was lmm;the anti-sagging was1250mmand each performance could meet the requirements.The high solid epoxy inner coating’s per unit volume cost was lower than the ordinary one.The third part is the design of the waterborne epoxy interior coating for container.Effects of different waterborne epoxy emulsions and curing agents, different dispersant, different defoamer, different kinds of anti-rust pigments and PVC were discussed in detail. The results show that:when waterborne epoxy emulsion D and curing agent J were chosen, the dosage of dispersant T was0.7%, the defoamer R2and R5were both chosen(the adding amount was respectively0.2%of the total formula),feldspar M was added, the formulation’s PVCwas about40%, the coating had the best performance, the fineness was40μm; the surface drying time was15min;the semi-hard drying time was12h;the pot life was4.5h;the hatch adhesion was level1;the impact resistance was50kg·cm; the flexibility was1mm;the anti-sagging was550mm;the anti-water time was1100h;the anti-salt water time was800h;the salt spray resistance was600h and each performance could meet the requirements.Now the cost of the waterborne epoxy inner coating was very high,and it would be promoted gradually.