Hydroxyethyl cellulose is widely used in latex paint, emulsion paint &coatings, how to use Hydroxyethyl cellulose in latex paint?
1. Add directly to the abrasive pigment
This method is the simplest and takes a short time. The detailed steps are as follows:
(1) Add appropriate purified water to the vat of the high-cutting agitator (in general, ethylene glycol, wetting agent and film-forming agent are added at this time)
(2) Start stirring at low speed and slowly add hydroxyethyl cellulose
(3) continue to stir until all particles are wet
(4) Adding mildew inhibitor, pH adjuster, etc.
(5) Stir until all the hydroxyethyl cellulose is completely dissolved (the viscosity of the solution is significantly increased) before adding the other components in the formulation and grinding until the lacquer is formed.
2. equipped with mother liquor
This method is first equipped with a higher concentration of mother liquor and then added to the latex paint. The advantage of this method is that it has greater flexibility and can be directly added to the finished paint, but it must be stored properly. The steps and methods are similar to the steps (1)-(4) in Method 1, except that the stirrer is not required to be high, and only a stirrer having sufficient power to keep the hydroxyethyl fibers uniformly dispersed in the solution is used. can. Continue stirring until completely dissolved into a viscous solution. It should be noted that the mold inhibitor must be added to the mother liquor as soon as possible.
3. with porridge
Since the organic solvent is a poor solvent for hydroxyethyl cellulose, these organic solvents can be used to provide a porridge. The most commonly used organic solvents such as ethylene glycol, propylene glycol, and film formers (such as hexane or diethylene glycol butyl acetate), ice water is also a poor solvent, so ice water is often used together with organic liquids It is equipped with porridge. The porridge-like hydroxyethyl cellulose can be directly added to the paint. Hydroxyethyl cellulose has been sufficiently soaked in porridge. When added to the paint, it dissolves immediately and thickens. After the addition, it is necessary to continuously stir until the hydroxyethyl cellulose is completely dissolved and homogeneous. Generally, the porridge is mixed with a portion of an organic solvent or ice water and a portion of hydroxyethyl cellulose. After about 5 to 30 minutes, the hydroxyethyl cellulose is hydrolyzed and remarkably rises. In general, the humidity of water in summer is too high and should not be used for porridge.
4. Precautions when using hydroxyethyl cellulose mother liquor
Since hydroxyethyl cellulose(HEC) is a treated granule, it is easy to handle and dissolve in water as long as the following matters are noted.
(1) Before and after the addition of hydroxyethylcellulose, stirring must be continued until the solution is completely clear and clear.
(2) It must be slowly sieved into the mixing tank. Do not add the hydroxyethyl cellulose which has been formed into a block and a spherical shape directly into the mixing tank.
(3) The water temperature and the pH value in the water have a significant relationship with the dissolution of hydroxyethyl cellulose, and special care must be taken.
(4) Do not add some alkaline substances to the mixture before the hydroxyethyl cellulose powder is wetted by water. Increasing the pH after soaking helps to dissolve.
(5) Add mold inhibitors as soon as possible.
(6) When using the high viscosity hydroxyethyl cellulose, the mother liquor concentration should not be higher than 2.5-3% (by weight), otherwise the mother liquor is difficult to handle.
Post time: Jan-03-2019