How much do you know about the water separation of water-based coatings?

The coating industry refers to the separation of solid pigments and fillers in coatings from the dispersion system as "water separation", or sinking.

As people's environmental protection requirements are getting higher and higher, the country has imposed strict limits on the VOC emissions of paints, and it is very important to develop pollution-free green paints.

At the same time, the pigment and filler particles are wetted by water in the water, causing the particles to agglomerate, and the micro-aggregates grow up and sink.

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2.

It can be seen from the above that the five types of dispersants are preferably polymer dispersants, especially polymer polyhydroxy stearic acid polyester and inorganic sodium hexametaphosphate.

2.

It can be seen from Table 3 that when the amount of dispersant is 0.

Take the above-mentioned polymer polyhydroxy stearic acid polyester and inorganic sodium hexametaphosphate at a ratio of 1:1 as a dispersion system, prepare emulsion paint according to the formula in Table 1, and investigate the pairing of different cellulose thickeners and liquid thickeners.

It can be seen from Table 4 that hydroxypropyl methylcellulose has the best effect on the preparation of "water separation".

Table 5 specifically discusses the influence of two commonly used liquid thickeners on the performance of "water separation" under the determination of other ingredients and dosages in the formula.

Second, the cellulose thickener should be hydroxypropyl methyl cellulose or hydroxyethyl cellulose with a larger molecular weight, with hydroxypropyl cellulose being the most preferred.

Third, the liquid thickener is preferably polyacrylic acid.
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