ACRYSOL™ RM-2020 E

• Excellent film build and applied hiding development
• Excellent flow and leveling
• High and sharp gloss
• Solvent-free* - low odor
• Excellent water and alkali resistance
• Use over a wide pH range
• Resistant to microbial attack
• Ease of handling

Solvent is not intentionally added and is not knowingly introduced from another raw material.

ACRYSOL™ RM-2020 E Rheology Modifier can be applied in a wide range of paint formulations including environmentally friendly ones with low volatile organic content,
formaldehyde and ammonia-free. It is particularly adapted for the following types of formulations:

• Solvent-free paints based on self film forming latex binders
• High opacity, high build coatings for exterior mineral substrates where improved hiding and excellent exterior durability (alkaline and water resistance) are essential.
• For interior wall paints, ACRYSOL™ RM-2020 E Rheology Modifier is compatible with all types of emulsions, allowing formulations with excellent technical performance as well as outstanding application properties,
• In gloss paints it is suggested to be used in combination with small particle size hydrophobic, acrylic gloss binders. The outstanding flow and leveling properties imparted by ACRYSOL™ RM-2020 E Rheology Modifier, combined with its strong gloss development, make it ideally suited for these applications.

Incorporation
ACRYSOL™ RM-2020 E Rheology Modifier is supplied as a pourable and pumpable liquid, free of solvent* and with very low odor. It can be added to the mill-base or during letdown.
Rheology Profile
ACRYSOL™ RM-2020 E Rheology Modifier imparts a Newtonian rheology profile to a paint. In gloss and semi-gloss paints this is ideal for giving the excellent flow and leveling properties required for brush application. For roller application, however, it is suggested to use it in combination with other thickeners. A more pronounced structure is obtained by adding some ACRYSOL™ SCT-275 Rheology Modifier, whereas a combination with ACRYSOL™ RM- 845 Rheology Modifier results in a smoother, less structured paint surface.
Dispersing Agents
In most formulations OROTAN™ 731A ER Pigment Dispersant (in matt to sheen paints) and OROTAN™ 1124 Pigment Dispersant (in semi-gloss paints) have been found to give good results in systems thickened with ACRYSOL™ RM-2020 E Rheology Modifier. For high-gloss paints, however, when enamel binders are used, OROTAN™ 681 Pigment Dispersant is suggested. It shows a superior overall performance and acting like flow modifiers, gives a greater degree of gloss reproducibility.
Paint pH Control
In some formulations, a high pH can cause polymer swelling. In turn, this can lead to high viscosity paints and instability. For this reason, paints thickened with ACRYSOL™RM-2020 E Rheology Modifier are best formulated at around pH 8.0. In ammonia free, low VOC formulations, it has been proven that potassium tetraphosphate (KTPP) maintains the pH and therefore improves the stability.

• ACRYSOL™ RM-2020 E Rheology Modifier is also suggested in a wide range of other paints (flat through high gloss).
• It can be used either alone or in combination with thickeners effective in the low shear range to reach the desired balance of flow and sag resistance.
• ACRYSOL™ RM-2020 E Rheology Modifier can be used as a sole thickener in high gloss paints in order to achieve enhanced flow properties.
• ACRYSOL™ RM-2020 E Rheology Modifier allows formulating paints with a Newtonian rheology profile and high film build, combined with excellent water and alkali resistance.
• The use of cosolvents for optimizing some formulations does not adversely affect the efficiency of ACRYSOL™ RM-2020 E Rheology Modifier.

The rheology modifying mechanism of ACRYSOL™ RM-2020 E Rheology Modifier is primarily associative.

1. Hydrophobic elements of the molecular structure tend to associate with other hydrophobic elements in the paint. These other hydrophobic elements are mostly latex binder and opaque polymers. \
2. Association with inorganic pigments is less frequent, but can exist. In the end, we get a network of associations, modifying the rheological profile of the paint and giving it the desired flow.
3. However, associative also means that the rheology of the paint is influenced by a whole range of elements other than the thickener itself. The following factors have a direct impact on the efficiency of ACRYSOL™ RM-2020 E Rheology Modifier in latex paints:

• Latex polymer particle size and distribution
• Latex polymer composition
• Surfactants and cosolvents

Latex Polymer Particle Size and Distribution

• The primary site for the associative characteristics of a rheology modifier is the surface of the binder particles. As a consequence, a greater surface area will lead to stronger association. Greater association leads to an increased efficiency. For a given volume of unimodal latex binder, a small particle size binder will have a greater total surface area than a larger particle size binder. Thus, the rheology modifier will work more efficiently with the smaller particle size binder.
• When a binder contains a distribution of particle sizes, the answer is not as clear. Here the distribution of particle sizes from large to small will determine the associative conditions more realistically than average particle size.

Latex Polymer Composition
ACRYSOL™ RM-2020 E Rheology Modifier is most efficient with hydrophobic latexes. This hydrophobicity may vary with the latex composition or the stabilizing system.
Surfactants

• The hydrophobic nature of surfactants allows them to compete with the associative capacity of the rheology modifier for the latex polymer surfaces. If the surfactant is able to displace the rheology modifier, the viscosity that is inherent to the rheology modifier polymer interaction can be reduced considerably.
• This means that special attention is needed for the type and amount of surfactant that is used, and for the combination with the binder. In addition, consideration must be given to the surfactants introduced with the colorant system. Predispersed colorants generally contain surfactants for stability and to facilitate color acceptance. Each colorant may have a different type and level of surfactant.

Cosolvents

• Water insoluble cosolvents, such as UCAR™ Filmer IBT, have little or no effect on the medium shear viscosity of a paint thickened with an associative thickener. Water soluble cosolvents, however, may reduce the low shear viscosity. Products such as ethylene glycol and propylene glycol will have the least effect, while butyl CARBITOL™ Solvent will have the greatest effect among the cosolvents tested to date.
• As in the case of surfactants, the level of cosolvent that is introduced with a predispersed colorant must be accounted for. One outcome of this cosolvent interaction is the potential to use these products for low shear viscosity adjustments. This can be done very effectively, but with a cost penalty and a potential reduction in water resistance due to the water solubility of these products.

Store products in tightly closed original containers at temperatures recommended on the product label.