Application method of hydroxyethyl cellulose in latex paint

1. Hydroxyethyl cellulose with porridge like phenology: because hydroxyethyl cellulose is not easily dissolved in organic solvents, some organic solvents can be used to equip porridge. Ice water is also a bad solvent, so it is often used in porridge with organic liquids. The hydroxyethyl cellulose of congee form can be added directly in emulsii paint. Hydroxyethyl cellulose has been saturated in porridge form. When added to the paint, it quickly dissolves and thickens. Keep stirring until hydroxyethyl cellulose is completely dispersed and dissolved. A typical porridge is made by mixing six parts of organic solvent or ice water with one part of hydroxyethyl cellulose. After about 5-30 minutes, the hydroxyethyl cellulose hydrolyzes and visibly rises. (It is suggested that the humidity of water in summer is too high to be used for porridge.)

2. Add hydroxyethyl cellulose directly to the grinding pigment: this method is simple and the time is short. Detailed methods are as follows:

(1) Add appropriate pure water in the VAT of high should cut agitator (generally, film forming additives and wetting agents are added at this time)

(2) Start to stir at low speed without stopping and slowly add hydroxyethyl cellulose evenly

(3) Continue to stir until all particles are evenly dispersed and soaked

(4) Add mildew inhibitor and adjust PH value

(5) Stir until all hydroxyethyl cellulose is completely dissolved (the viscosity of the solution increases significantly), then add other components in the formula, and grind until it becomes paint.

3 the hydroxyethyl cellulose with mother liquid waiting: this method is first equipped with a higher concentration of mother liquid, and then add latex paint, the advantage of this method is more flexible, can directly add paint finished products, but to appropriate storage. Steps and methods are similar to steps (1) – (4) in Method 2, except that a high cutting agitator is not required and only some aggers with sufficient power to keep the hydroxyethyl fibers evenly dispersed in the solution are used. Continue stirring until it completely dissolves into a thick solution. Note that: antimildew agent must be added as soon as possible in the paint mother liquor.

4 Matters needing attention when equipping hydroxyethyl cellulose mother liquor

Since hydroxyethyl cellulose is a treated granular powder, it is easy to handle and dissolve in water with the following precautions.

(1) Before and after adding hydroxyethyl cellulose, must keep stirring, until the solution is completely transparent and clear.

(2) It is necessary to sieve the hydroxyethyl cellulose into the stirring tank slowly. Do not add it in large quantities or directly into the stirring tank.

(3) The solubility of hydroxyethyl cellulose is obviously related to water temperature and pH value of water, so special attention should be paid to it.

(4) Do not add some basic substances to the mixture before hydroxyethyl cellulose powder is soaked with water. Raising the pH after soaking helps dissolve.

(5) As far as possible, early addition of mildew inhibitor.

(6) When using high viscosity hydroxyethyl cellulose, the concentration of mother liquor should not be higher than 2.5-3% (by weight), otherwise mother liquor is difficult to operate.

Factors affecting the viscosity of latex paint:?

(1) Due to excessive stirring and excessive humidity when dispersing.

(2) the amount of other natural thickeners in the paint formula and the proportion of the amount with hydroxyethyl cellulose.)

(3) the amount of surface activator and water in the paint formula is consistent.

(4 in the synthesis of latex, residual catalyst oxide content of the number.

Microbial erosion of thickener.

6 in the process of making paint, the order of steps to add thickener is appropriate.

?The more residual air bubbles in the paint, the higher the viscosity