Water-based rheology additives
The rheological additives of the aqueous system are montmorillonite clay-based rheological additives which have been purified, modified and then mixed through and pass.
The rheology additives of aqueous systems can be used in daily chemicals, mainly for adsorption, cleaning, suspension, stabilization, thixotropy, thickening and other functions. Used for toothpaste is mainly thickening, suspension friction agent, polishing particles and prevention of toothpaste solid-liquid component separation and other functions. Its performance directly affects the stability of toothpaste. Used in cosmetics to stabilize emulsifiers, which can reduce the amount of emulsifiers. At the same time, it can also be used for soap-type milk to increase fluidity and improve the whiteness of the paste after storage.
Rheology additives for aqueous systems can be used in coatings, mainly as dispersion suspension, thixotropy, thickening, suspension anti-settling agent and rheology additive for aqueous systems. The suspension anti-settling agent can change the suspension of water-based coatings. And adding an appropriate amount of montmorillonite to the coating can make the coating not easy to precipitate, delamination, uniform color to improve the suspension stability of the coating. Rheology additives for the coating contradictory sagging and leveling two properties to obtain waterborne system rheology additives can be used for balance. When the coating is stored, the rheology additive forms a loose structure inside it, after construction, by external force, the internal structure is damaged The coating is easy to level, to a certain stage of the wet film inside and slowly restore the loose network structure, and is conducive to preventing sagging.
Rheology additives in aqueous systems can be used in agricultural chemicals, mainly to stabilize suspension and delay release. The reasons that the pesticides used in pesticides are mainly montmorillonite with a large specific surface area, which can adsorb the active components of pesticides and prepare slow-release pesticide preparations, while forming a highly dispersed and highly stable suspension in water.
Mechanism of action of waterborne rheology additives:
The crystal structure of montmorillonite is a 2:1 type layered silicate composed of two layers of silicon-oxygen tetrahedral crystal layer sandwiched between an aluminum (magnesium) oxygen octahedral crystal layer. Montmorillonite structure contains a large number of hydroxyl groups, strong hydrophilicity, and significant water absorption and expansion characteristics. The expansion of montmorillonite is mainly based on the hydration of interlaminar cations. Water molecules enter the crystal layer, causing their layer spacing to increase. The sheet is peeled off, and three particle association patterns appear in the suspension: face-to-face, edge-to-side, edge-to-edge. Face-to-face association leads to an increase in particle size, side-to-side, edge-to-edge association to form a three-dimensional network structure.
Product performance indicators:
Model number | TOP-T230 | TOP-T250 | TOP-T260 | TOP-T270 | TOP-T650 | TOP-T655 | TOP-T660 |
Appearance | Off-white or light off-white powder |
Particle size(mesh 200)% | ≥95 |
Moisture/% | <10% |
Density (g/cm3) | 2.2 | 2.2 | 1.6 | 1.6 |
Viscosity | ≥100 | ≥100 | ≥150 | ≥150 | ≥3000 | ≥5000 | ≥3000 |
Whiteness | 65 | 70 | 70 | 60 | 70 | 70 | 70 |
TOP-T2 series thixotropic montmorillonite is a refined and modified montmorillonite clay, which has excellent water absorption expansion, dispersion suspension, thixotropy, thickening, and is a suspension anti-settling agent and rheology additive for aqueous systems.
TOP-T650 and TOP-T655 thixotropic thickening montmorillonite are montmorillonite clays that have been refined and purified and organically modified, and thickening groups are introduced to enhance the thickening effect on the basis of its good thixotropy.
TOP-T660 ultra-disperse suspended montmorillonite is a refined and organically modified montmorillonite clay, which introduces functional groups to make it super easy to disperse, which can provide high viscosity, excellent sagging resistance and increase spraying effect at low and medium shear speeds.
Application Areas:
Latex coatings, foundry coatings, industrial coatings, modeling coatings, thick paste coatings, sealants, water-based inks, water-based pigments, ceramic glazes, cement systems, agricultural chemicals
Key Features:
TOP-T2 series has excellent thixotropic performance, easy coating surface smoothness, increased sagging resistance, and enhanced anti-settling effect of emulsion.
TOP-T650, TOP-T655 excellent thixotropy, high efficiency thickener, provide high viscosity, viscosity thermal stability.
TOP-T660 provides excellent low to medium shear viscosity, shear dilution and stable suspension, increased spraying effect, excellent sagging resistance.
Method of Application:
It is recommended to use 8-12wt% pre-gel to add, that is, under low-speed stirring conditions, slowly add water-based montmorillonite to water, and then slowly add the sample to the water under the condition of stirring, stir at 2000rpm for 30min, so that the solution is fully dispersed to form a uniform gel, and then stand for 12-24h to completely hydrate the montmorillonite and add it to the water-based coating. Direct or grind-dispersion methods can also be used, and the order of addition can be determined on a case-by-case basis.
Add Amount:
Typically it is 0.3-1% of the total formulation, mainly depending on suspension, rheological properties or viscosity.