Research and development of high-performance water-based anti-corrosion coatings has become imperative!

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com。202071，、VOCs。VOCs，，2013VOCs＜300 g/L，1998VOCs＜450 g/L，（GB 30981－2014）VOCs390～720g/L。

，VOC，，。、，50% ，10%。，。

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1 

(1)

、、、、，，，，20 μm，，，。

(2)

、，，、，；，。1。

1

(3)

，：，80 ℃ 15min， 120℃ 25min，180℃30min，。

2

(1)

。，、，、、，，。-，，、。，，，。

（g/Eq1600~2000）（EPIKOTE 3540-WY-55），，，。（CTW-6062），（g/Eq910～1020），。

，（EPIKOTE 3540-WY-55）（CTW-6062）， 2，2。

2

21，（EPIKOTE 3540-WY-55），，（5℃），。（CTW-6062），，，。2EPIKOTE 3540-WY-55CTW-60627:33:7，10%HCl 16d。

2，CTW-6062，，CTW-6062，。CTW-6062，，。，（EPIKOTE 3540-WY-55）（CTW-6062）7:3，。，m（EPIKOTE 3540-WY-55）∶m（CTW-6062）7:3。

(2)

，：（CYMEL 303、CYMEL 350）、（CYMEL 325、CYMEL 327）、。

。，CYMEL 303、 CYEML 3501% CYCAT 4040，， 3。

3

3，CYMEL 303、CYMEL 350，，VOC。CYMEL 325、CYMEL 327/，，，，VOC ，。CYM EL303CYM EL350，CYM EL350CYMEL 303，，。，CYMEL 303。

(3)

The ratio of pigment to base (P/B) is a factor that cannot be ignored in the formulation of heavy-duty anti-corrosion coatings.

When the pigment-to-base ratio is low, the filling degree of the resin and curing agent is lower, resulting in lower compactness of the coating system, so the permeability of the corrosion-resistant medium will decrease, the chemical resistance will be partially reduced, and the cost of the coating will increase; If the base ratio is too high, the pigments and fillers cannot be completely covered by the resin, and part of the pigments and fillers particles are free from the voids of the resin space structure, which affects the bonding between the coating and the substrate, and other resistance and physical and mechanical properties will also be reduced.
Use water-based epoxy emulsion EPIKOTE 3540-WY-55, CTW-6062 as the base resin of water-based coatings, choose CYMEL 303 as the curing agent, and keep the content of other components unchanged.
Adjust the paint-to-base ratio through experiments, and choose the one under the optimal conditions.
Yan Kibi, the results are shown in Table 4.

Table 4 The effect of pigment-to-base ratio on coating performance

It can be seen from Table 4 that when the pigment-to-base ratio>1, the water resistance and hydrochloric acid resistance become worse; when the pigment-to-base ratio is 0.

2, the water resistance and acid resistance are partially improved, but the cost of the coating is higher; In the case of mechanical properties and resistance to chemical media, the overall performance is better when the color-to-base ratio is 0.
6.

(4) The effect of anti-flash rust agent on the anti-corrosion performance of the coating

When the water-based paint dries on the surface of the substrate, it is prone to flash rust.

Adding anti-flash rust agent can inhibit corrosion.
During the experiment, the effect of different anti-flash rust agents on performance was investigated.
The experimental results are shown in Table 5.

Table 5 Effect of anti-flash rust agent on coating performance

It can be seen from Table 5 that sodium nitrite is the most commonly used anti-flash rust additive for water-based anti-corrosion coatings.

Since the flash rust phenomenon is generally caused by electrochemical effects, the use of such reducing substances to release negative charges to the metal base The anti-rust of the material is of great help.
When the dosage is 0.
2% of the total weight of the formula, the flash rust can be inhibited.
However, due to the high ionicity of such substances, the water resistance of the paint film is significantly deteriorated due to the large amount of addition.
Raybo 60 is a mixture of organic zinc chelate and sodium nitrite.
Its anti-rust ability is slightly worse than that of sodium nitrite alone.

FA-179 is an organic zinc chelate compound.

The addition of FA-179 has little effect on the water resistance of the coating, but the anti-flash rust ability is poor.

(5) Performance of waterborne epoxy anticorrosive coating

Based on the above discussion results, a waterborne epoxy anticorrosive coating with excellent performance has been developed.

The performance test results are shown in Table 6.

Table 6 Main properties of waterborne epoxy anticorrosive coatings

Conclusion

(1) Take m (EPIKOTE 3540-WY-55): m (CTW-6062) as the base material at 7:3, use amino resin CYMEL 303 as the curing agent, the ratio of pigment to base is 0.

6, and the anti-flash rust agent is EMDOX ® The dosage of 2K HE is 0.

(2) The developed waterborne epoxy anticorrosive coating has good physical and mechanical properties, excellent anticorrosion, chemical resistance and temperature resistance.

At the same time, the paint uses water as the dispersion medium and has a low VOC content.