RHOPLEX EI-3500 Polymer Emulsion for Fast-Setting Textured Finishes

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1 RHOPLEX EI-3500 Polymer Emulsion for Fast-Setting Textured Finishes Description RHOPLEX EI-3500 emulsion is an all-acrylic waterborne polymer providing fast-set characteristics for textured finishes, especially when application occurs under marginal weather conditions. Benefits of RHOPLEX EI-3500 Versus Conventional Waterborne Polymers in Textured Finishes Extended application seasons and locations Labor savings reduces the time needed to complete an application. Same-Day finish applications (One- Day Wall) Early washout resistance fewer complaints of washout Fast surface set and set through properties without significant surface skinning Excellent acrylic durability Typical Properties These properties are typical but do not constitute specifications. Solids content, % by weight C, cps 100 max ph 10 to 10.2 Density, lbs./gal MFFT ( C) 17 Bulking Value, gals./lb. Wet Dry Formulating and Manufacturing Textured Coatings The level of RHOPLEX EI-3500 emulsion used in a textured finish must be determined to deliver the required level of performance. In addition, formulating and manufacturing principles associated with RHOPLEX EI-3500 emulsion are unique to fast setting technology. The fast setting characteristics of RHOPLEX EI-3500 emulsion require careful consideration when formulating to ensure delivery of maximum benefits from the technology. What is typically required for the manufacture of quick set textured coatings, in contrast to conventional textured coatings, is a low speed, low shear operation with a slight vortex. This procedure is necessary to avoid excessive heat build-up during the mixing stage, which otherwise may result in skinning of the formulation due to the heat and loss of ammonia. In addition, there are other formulation variables and ingredients that can make the difference between a marginally performing product and a superior one. The following summary offers some guidelines to achieving good quality and durability. Polymer Level The properties of the finish, such as color fastness and resistance to water, chalking, cracking, and erosion are influenced by the amount of polymer used in the formulation. Particle size, density, particle distribution, and particle shape of the extenders, pigments, and very small particle size rheology modifiers like clay, influence the level of polymer, or binder, needed for adequate performance and durability of the finish. Increasing pigment and extender surface area increases binder demand. One of the principal parameters that can be used to measure the performance of a finish is the pigment volume concentration (PVC). While percent polymer is a convenient method to estimate the quality of an EIFS finish, PVC is better. PVC is defined as the ratio of the dry pigment volume to the volume of dry pigment, plus the volume of dry polymer. For the finish coat, the PVC is calculated by dividing the gallons of pigment and extender solids by

2 the total gallons of finish solids and multiplying by 100. As the PVC increases, the amount of polymer in the finish decreases, and resistance to cracking, chalking, erosion, and color fastness is reduced. Studies conducted on conventional textured finishes to determine the effect of PVC on the performance and durability of the finishes have shown that a PVC between 70% (15% solid polymer on the dry finish weight) and 79% (10% solid polymer on dry finish weight) provides the best balance of performance properties. Above this PVC, the level of performance begins to drop off as the PVC is increased. If the PVC is too high, the amount of binder in the finish becomes insufficient to hold all the pigments and extenders together efficiently. The ability of the polymer to bind all these materials is stretched beyond its capability and at some point the finish begins to degrade as evidenced by excessive chalking, cracking, and poor color retention. Coalescing Agent Adequate amounts of coalescent are needed to produce a tough polymer film under a variety of curing or weather conditions. A properly coalesced coating is essential for good resistance to cracking and good exterior durability. For a RHOPLEX EI-3500 textured finish, use Texanol at approximately 8-10% on polymer solids to insure adequate film formation. Thickener For a textured finish coat based on RHOPLEX EI-3500 emulsion, use ACRYSOL ASE-60, an acid-containing, crosslinked acrylic emulsion copolymer. When the emulsion is diluted with water and neutralized with a base, such as ammonium hydroxide, each emulsion particle swells and the viscosity increases. The level of ACRYSOL ASE-60 rheology modifier needed will depend on the viscosity required and the formulation. The ACRYSOL ASE-60 should be diluted with water and slowly added to the mixer with good agitation. The materials in the mixer should be neutralized with base prior to adding the diluted ACRYSOL ASE-60 solution. The enclosed EIFS finish formulation uses approximately 2.6% ACRYSOL ASE-60 (solid) on the solids of RHOPLEX EI-3500 emulsion to achieve a viscosity range of paste units measured on a Stormer Viscometer. Thixotropic Agent Attagel 50, an attapulgite clay, is recommended for adjusting the flow properties of the finishes. The flow properties undergo a reduction in consistency (shear thinning) when troweled to facilitate ease of application, and recovers to its original consistency when shear is removed. The Attagel 50 also prevents slump and sag once the finish has been applied. Attagel 50 is preferred over some other commercial clay extenders because it is very efficient at low use levels. High levels of any clay can contribute to yellowing, chalking, and adversely affect color fastness. Wet Edge Agents Low levels of ethylene glycol or propylene glycol can be added to textured finishes based on RHOPLEX EI-3500 emulsion to allow for sufficient open time to trowel the finish on the wall and come back and texture it. The glycol retards skin formation of the finish. Typically, 3-8 pounds/100 gallons of ethylene glycol or approximately 5-10 pounds/100 gallons of propylene glycol are normally adequate to achieve good open time. These materials are water sensitive and their use must be balanced between open time and drying time. Titanium Dioxide Titanium dioxide is a pigment added to the EIFS finish as a whitening agent and for tinting bases. To be effective, the titanium dioxide needs to be properly dispersed. If dispersant is needed, TAMOL 901 may be used. Neutralization Ammonium hydroxide should be used to neutralize textured finishes based on RHOPLEX EI-3500 emulsion. The use of other neutralizers may impact the fast set capabilities of such finishes. The ph of the formulation should be maintained at no less than 9.5 to ensure adequate storage stability. Defoamer A defoamer is used for suppressing formation of foam during manufacture, for filling containers, tinting, and

3 applying textured finishes. A defoamer is added to cementitious admixtures to maximize the density and subsequently the performance of the base coat/adhesive. Foamaster NXZ is recommended with RHOPLEX EI emulsion. Extenders Graded silica sands are typically the primary extenders used in EIFS finishes. In a random finish, using two different particle size sands yields good particle packing and the desired texture appearance. These extenders increase the solids content of the formulation. Silica sands usually have a narrow particle size distribution and may not self pack. Sufficient material may be needed to fill in voids between the silica sands. In some formulations, for example the 79% PVC finish in this brochure, a fine particle size extender such as Minex 4 can be used. The level of fine filler used needs to be determined, since excessive amounts can result in cracking of the finish. When fine particle size extenders are used, the polymer level may need to be increased to account for the greater surface area to maintain performance and durability. Minex 4 is preferred over other fine fillers, such as calcium carbonates, because Minex 4 provides greater resistance to frosting in darker colors. Calcium carbonate is susceptible to acid rain, so a dark colored finish made with calcium carbonate could leave white calcium deposits on the surface after repeated rain. These white deposits are often referred to as frosting. Other Considerations Coalescent should be added slowly into the vortex to avoid polymer flocculation. Pre-emulsification of the coalescent (separately under higher shear) may be beneficial to ensure homogeneous incorporation. If a wetting agent is needed, Surfynol CT-136 may be used. Avoid using blends of other emulsions with RHOPLEX EI-3500, as this may affect the fast set properties. The storage temperature of textured finishes based on RHOPLEX EI-3500 emulsion should be kept between 32 F and 100 F. Because setting may occur too quickly at higher temperatures for textured coatings based on RHOPLEX EI emulsion, it is recommended for best performance that such products be used when surface temperature is between 40º F and 55º F. Textured Finish Formulation DV-0520B Based on RHOPLEX EI-3500 Material Pounds Gallons RHOPLEX EI Propylene Glycol Foamaster NXZ Surfynol CT TAMOL Ti-Pure R Temisca #15 sand Minex Unimin sand Attagel ROZONE Texanol Ammonia (28%) Premix ACRYSOL ASE Water Premix Sub-total Foamaster NXZ Totals => VOC: 37.3 g/l Dispersant: 0.1% Density: lb/gal Coalescent: 10.0% Solvent: 1.4% Levels without additives: PVC: 79.0% Volume Solids: 67.9% Weight Solids: 83.2% Levels with additives: Volume Solids: 69.0% Weight Solids: 83.9%

4 Test Procedures Washout Resistance: 6 x 1.5 x 1/16 thick finish coats over 6 x 8 EPS board or basecoat with five films per board and a separation of 0.25 between each sample. Film thicknesses, widths, and separations were kept constant throughout the measurements since previous work had shown that these factors all affect the time to washout. Basecoats were applied directly over the EPS board. Finish coats were applied over EPS board coated with cementitious basecoat with mesh embedded. The films were allowed to cure for varying lengths of time under the following conditions: A. Room temperature = 75 F/50% R.H. B. Hot pack environmental chamber = 45 F/75% R.H. Times to failure were measured by placing the samples under a sprinkler head which delivers 180 gallons/hour of water spray across the sample surface. Times to failure were reported when the textured coatings began to erode and the time until the cementitious basecoat is visible. The test was terminated after two hours, and samples were considered to pass if there was no change in their appearance. This time was chosen because a basecoat cured for 120 minutes was topcoatable and so that several samples could be run in one day. Performance Properties of a Textured Finish Based on RHOPLEX EI-3500 Emulsion Early Washout Resistance 1, 2 Conventional Latex Finish RHOPLEX EI-3500 Finish (DV-0520B) Time to Washout, Minutes 75 F/50% RH 1 hr. Cure 1/2 2/5 2 hr. Cure 11/18 33/35 4 hr. Cure Pass Pass 45 F/75% RH 4 hr. Cure 0/2 1/3 8 hr. Cure 0/5 2/5 16 hr. Cure 1/5 Pass 24 hr. Cure Pass Pass Mandrel Bend Flexibility (ASTM D-522) 75 F/50% RH Pass 2 ; Fail 1 Pass 1 ; Fail 1/2 40 F/50% RH Pass 4 ; Fail 2 Fail 4 Heat Stability (10 days at 60 C) P P Test terminated after 120 min. Reported as minutes until surface of coating begins to erode/ Minutes until basecoat is visible Material Function Supplier RHOPLEX EI-3500 Binder Rohm and Haas Foamaster NXZ Defoamer Sidobre Sinnova S.A. Surfynol CT-136 Surfactant Air Products TAMOL 901 Dispersant Rohm and Haas Ti-Pure R-942 Titanium Dioxide DuPont Temisca #15 sand Functional Pigment Temisca Minex 4 Extender Unimin Unimin sand Functional Pigment Unimin Attagel 50 Extender BASF Texanol Coalescent Eastman ACRYSOL ASE-60 Thickener Rohm and Haas Material Safety Data Sheets Rohm and Haas Material Safety Data Sheets (MSDS) contain pertinent information that you may need to protect your employees and customers against any known health or safety hazards associated with our products. Under the OSHA Hazard Communication Standard, workers must have access to and understand MSDS on all hazardous substances to which they are exposed. Thus, it is important that you provide appropriate training and information to your employees and make sure they have available to them MSDS on any hazardous products in their workplace.

5 Rohm and Haas Company sends MSDS for all its products, whether or not they are considered OSHA hazardous, to both the "bill to" and/or "ship to" locations of all its customers upon initial shipment, including samples. If you do not have access to one of these MSDS, please contact your local Rohm and Haas representative for an additional copy. Updated MSDS are sent upon revision to all customers of record. In addition, MSDS are sent annually to all customers receiving products deemed hazardous under the Superfund Amendments and Reauthorization Act. MSDS should be obtained from your suppliers of other materials recommended in this bulletin. Rohm and Haas Company is a member of the American Chemistry Council and is committed to ACC's Responsible Care Program. ACRYSOL, RHOPLEX, ROZONE and TAMOL are trademarks of Rohm and Haas Company, or of its subsidiaries or affiliates. These suggestions and data are based on information we believe to be reliable. They are offered in good faith, but without guarantee, as conditions and methods of use of our products are beyond our control. We recommend that the prospective user determine the suitability of our materials and suggestions before adopting them on a commercial scale. Suggestions for uses of our products or the inclusion of descriptive material from patents and the citation of specific patents in this publication should not be understood as recommending the use of our products in violation of any patent or as permission or license to use any patents of the Rohm and Haas Company. Rohm and Haas, 2009 All rights reserved. October A565