In order to obtain excellent applicability, it is necessary to use rheological additives to adjust the rheological properties of latex paint, and it is also necessary to retain the thixotropic fluid characteristics of latex paint. Improve flow characteristics by introducing rheological additives, rationally combine different types of thickeners, obtain satisfactory apparent viscosity in different shear regions, and achieve coordination between low shear and high shear viscosity. In this paper, the influence of the structure, dosage and combination of rheological additives on the rheological properties of latex paints is studied.
Preparation Process
Put rutile titanium dioxide, light calcium carbonate, pigment dispersant, most of deionized water, ethylene glycol, bactericidal antifungal agent, half amount of defoamer, pH stabilizer into the high-speed disperser, and disperse to a fineness of 40 After Hm, add the remaining half amount of defoamer, emulsion resin, film-forming aid and pre-mixed hydroxyethyl cellulose solution, and finally add a set amount of rheology additive, and stir until the viscosity is stable.
Test Methods
Leveling Determination
Use Leneta ASTM-4 type coater and Leneta 7BS&L paper, according to ASTM D4062-81.
Sag Resistance Determination
Use Leneta ASTM-4 type coater and Leneta 7BS&L paper, according to ASTM D4400-84.
Test Results
The "associative" thickener has an obvious weakening effect on the low shear viscosity (LS V), which reflects that the paint film is easier to level and sag.
