Elastomeric acrylic coatings are an economical alternative to extend the life of an existing roof. Advances in polymer chemistry have resulted in elastomeric coatings that provide lasting restoration, retrofit, or repair. This “liquid-applied membrane” completely bonds to the surface as it dries, yet remains “elastomeric.” It stretches as the substrate moves and then returns to its original shape without deformation. What more? Ultraflex is 1000% stretchable, an ultimate protection to roofs and podium. Weathered and deteriorated masonry structures have long represented one of the most difficult maintenance challenges for the contractor. In the past five years, recoating with an elastomeric wall coating has become one method for repairing these surfaces.
The most important performance properties of a quality elastomeric wall coating are flexibility over a broad range of temperatures, resistance to dirt pick-up and hydrolysis, and ultraviolet stability. These coatings need to allow water vapor to escape while blocking the transmission of bulk water, CO₂ and chloride ions. In addition, even a high-quality coating must be applied over a sound, properly prepared surface for outstanding durability. The purpose of rehabilitating masonry structures is to protect, beautify, and restore them to their original luster. If the coating used for the renovation does not have the performance properties listed above, it may soon crack, become dirty, and potentially peel off the substrate. Many applicators probably have seen some or all of these problems. Thus, it is important for contractors to understand the best combination of performance properties in an elastomeric coating like Ultraflex.

Comparing Elastomeric Wall Coatings
There are typically three types of polymers that can be formulated into coatings that are labeled as Ultraflex elastomeric coatings — 100 percent acrylic, styrenated acrylic, and vinyl acetate-containing copolymers. There are critical differences between the three types of binders in elasticity, resistance to hydrolysis, and ultraviolet stability. One hundred percent acrylic elastomeric emulsion polymers are the only products that have demonstrated the ability to provide an elastomeric coating with all three properties. Of the commercially available binders, neither the styrene acrylic nor the vinyl acetate polymers are as flexible at low temperatures as the 100 percent elastomeric binders like Ultraflex
To obtain acceptable performance when using styrene acrylic and vinyl acetate polymers, the formulator may incorporate an external plasticizer into the coating. Although an external plasticizer can improve flexibility, there are serious drawbacks to its use. First, typical plasticizers will only enhance elongation and flexibility in a relatively narrow range of temperatures. If the ambient temperatures run outside this range on the high side, the coating risks losing its recovery properties, becomes gummy, and can flow apart under the stresses caused by the dimensional fluctuations of cracks in the masonry. In addition to a limited range of effective operating temperatures, external plasticizers suffer from another serious disadvantage — they migrate from the interior of the coating film to the surface and eventually out of the coating entirely. This phenomenon has a detrimental effect on the formulation’s dirt resistance. Dirt from the air tends to adhere, seriously detracting from the coating’s appearance. Elastomeric coatings like Ultraflex are specially designed to eliminate such limitations, delivering lasting flexibility and durability. For projects demanding performance and protection, Ultraflex remains a top-tier solution.

Why Use Cool Roof Even Sandwich Application?
Thermal Properties:
A cool roof can be desirable to a building owner for several reasons. Ultraflex, a high-performance elastomeric coating, enhances cool roof performance and offers long-term durability. Cool roofs can:
• Reduce energy bill by decreasing air conditioning needs,
• Improve indoor thermal comfort for spaces that are not air conditioned.
• Decrease roof operating temperature, which may extend roof service life.

In many cases, cool roofs cost about the same as non-cool alternatives. The energy cost savings you can realize from a cool roof with Ultraflex depends on many factors, including local climate; the amount of insulation in your roof; how your building is used; energy prices; and the type and efficiency of your heating and cooling systems.

Ultraflex based cool roofs can also benefit the environment, and policymakers may issue cool roof regulations to provide these benefits to society. Cool roofs with Ultraflex can:
• Reduce local air temperatures, which improve air quality and slow smog formation;
• Reduce peak electric power demand, which can help prevent power outages;
• Reduce power plant emissions, including carbon dioxide, sulfur dioxide, nitrogen oxides, and mercury by reducing cooling energy in buildings; and
• Reduce heat trapped in the atmosphere by reflecting more sunlight back into space, which can slow climate change.

Reducing the roof’s temperature with a cool roof can also increase the need for heating during heating seasons. Later sections of this report show you how to evaluate the resulting cost savings for your building.

Solar Reflectance is the fraction of the sunlight that a surface reflects. Sunlight that is not reflected is absorbed as heat. Solar reflectance is measured on a scale of 0 to 1. For example, a surface that reflects 55% of sunlight has a solar reflectance of 0.55. Most dark roof materials reflect 5 to 20% of incoming sunlight, while light-colored roof materials typically reflect 55 to 90%. Ultraflex is engineered with high solar reflectance values, helping reduce heat absorption significantly. Solar reflectance has the biggest effect on keeping your roof cool in the sun.

Thermal Reflectance describes how efficiently a surface cools itself by emitting thermal radiation. Thermal emittance is measured on a scale of 0 to 1, where a value of 1 indicates a perfectly efficient emitter. Nearly all nonmetallic surfaces have high thermal emittance, usually between 0.80 and 0.95, that helps them cool down. Bare, shiny metal surfaces, like aluminum foil, have low thermal emittance, which helps them stay warm. A bare metal surface that reflects as much sunlight as a white surface will stay warmer in the sun because it emits less thermal radiation. With its high thermal emittance properties, Ultraflex promotes effective heat dissipation, contributing to overall energy savings.

Solar Reflectance Index (SRI) is another metric for comparing the “coolness” of roof surfaces. It is calculated from solar reflectance and thermal emittance values. The higher the SRI, the cooler the roof will be in the sun. For example, a clean black roof could have an SRI of 0, while a clean white roof could have an SRI of 100. Dark roofs usually have an SRI less than 20. Coatings like Ultraflex are designed to maximize SRI, keeping building interiors cooler and reducing the urban heat island effect.

Mechanical Properties
The graph has been prepared to demonstrate the relationships among tensile strength, elongation and installed film thickness. The trend clearly shows that elongation will increase and tensile strength will decrease as the film thickness is increased. This flexibility is important because roofs tend to expand and contract with building movement, changes in temperature and thermal shocks caused by severe weather. In these situations, it is important for the coating to move with the roof and not provide any routes for the sun to attack the surface underneath. Ultraflex, with its high-performance elastomeric formulation, is designed to handle such dynamic roof movements effectively. Also, if a crack were to form in the substrate, the coating would be expected to bridge the crack and continue to provide a seamless surface. While a coating at 20 dry mils (0.500 millimeter) will stretch by almost 200% in this case, it is important to note that at 5 dry mils (0.127 millimeter), the same coating will only have about 140% elongation. Keep in mind that ASTM D6083 requires conducting all mechanical testing with films that have a dry film thickness of 20 +/- 2 mils (0.5 mm +/- 0.050 mm). This provides a level playing field for the evaluation of different coatings, but is not always consistent with what will be installed on a roof. All premium paints which normally have thickness of 50 microns (0.05mm) will not perform as elastomeric (as claimed in the market), hence crack cannot be taken care of. Ultraflex meets ASTM D6083 standards and is specifically engineered for consistent film build and flexibility.

Proper Hiding of Coating
Another key reason for proper film thickness is to effectively protect the roof substrate from harmful solar ultraviolet (UV) rays. These rays, which make up only about 10% of the energy from the sun, cause most of the degradation in the roofing membranes coatings are designed to protect. The main opacifier in an elastomeric roof coating is titanium dioxide (TiO₂), which works by efficiently scattering the sun’s energy and blocking it from reaching the substrate. However, this can only be accomplished by having enough UV blockers present to prevent the UV energy from reaching the substrate. A quick test of this theory can be run by making drawdown of various thicknesses over black surfaces. You will see that at lower film thicknesses, the black surface will show through the coating and make the white coating appear gray. At higher film thicknesses, this effect will disappear as the coating completely hides the surface below it. Ultraflex provides excellent opacity and hiding power, ensuring maximum UV shielding and protection at recommended

Weathering Effects:
A fact of life in the roofing business is that all roofs will fail over time due to weather effects and exposure to the sun’s UV rays. In this respect, acrylic elastomeric roof coatings are no different than EPDM, asphalt or thermoplastic sheets – over time, the elements will take their toll by breaking down the chemical components. In elastomeric roof coatings specifically, the UV energy from the sun will slowly break down the acrylic resin over time and microscopic layers of the coating will slowly wash away.
Coatings applied at greater thicknesses have proven to perform better over the long term. The coating applied at 5 dry mils did not adequately protect the foam from the sun, and consequently the foam broke down into a powder. On the other hand, after 12 years, the 30-dry mil (0.76 mm) samples has still unmarred and providing protection to the foam below. These examples illustrate why a thicker membrane or coating is expected to withstand the elements for a longer period of time, and why thickness is often the main driver in warranty length for many different types of roofing system. Ultraflex, when applied at the specified thickness, has demonstrated superior long-term weathering resistance and protection performance in field tests.

Dirt Accumulation
Some roof coatings do tend to accumulate dirt, which will cut down on their solar reflectance. Keep in mind, however, that this accumulation of dirt does not affect the quality of the product itself or its ability to provide you with leak-free performance. Ultraflex has enhanced dirt pickup resistance, maintaining its reflectivity and appearance longer, even in harsh environments. But you cannot escape the fact that all roofing systems – coatings or otherwise – accumulate dirt. The dirt is in the air, it is in the rain. It cannot be avoided.
A typical solar reflectance rate of 0.85 to 0.90 will drop to about 0.70 to 0.75 during the first several months of a roof restoration system being installed. After that it levels off to around 0.60 to 0.70. That’s a reduction of around 25 to 30 percent. A significant number to be sure, but not the end of the world. Regular cleaning is required to avoid dust collection on roofs. Even if such things are not possible, products like Ultraflex are designed to repel dirt at its base. But the technology continues to advance and this issue is becoming less and less important. It cannot go away completely but it is becoming less and less of an issue. We are almost there as it is.

Other Properties:
High Fluid Resistance – Use of less fluid-resistant elastomeric coating for bulk of component, followed by post cure addition of coating provides excellent fluid resistance of overall system. Rainshield, RhinoStrong and SuperFlex Plus provide excellent resistance to lubricating oils and transmission fluids.
Excellent Ozone Resistance – Allows use of less ozone-resistant elastomer for bulk of component, followed by post cure addition of coating, resulting in excellent ozone resistance of coated system. Ultraflex, with its advanced polymer backbone, performs exceptionally well under ozone-rich conditions.
Excellent Mechanical Properties – Strong adhesion to substrate and elongation of up to 1500% – properly applied coating does not crack or peel. In laboratory testing, coating like Ultraflex demonstrated that it will not peel or crack prior to substrate cracking.
Adhesion of Elastomeric Coating – Adhesion of the elastomeric coating will eliminate blistering in areas where there is ponding water. Illustrates the improvement in adhesion of both a new and aged EPDM membrane that was cleaned with a new technology product.
Substrates and Climatic Factors – While all exterior building materials are susceptible to expansion and contraction due to climatic changes, concrete and stucco are particularly vulnerable because of their composition and use of dissimilar building materials. Once the water migrates out during curing, the hard material left behind results in a less than flexible surface and shrinkage cracks, leaving the building exposed to moisture penetration. Consequently, elastomeric wall coatings like Ultraflex are ideal for masonry, concrete, and stucco surfaces.
Hence, elastomeric coatings, with proper technology, can give 100% waterproofing and very high cool effects.

For further details on Ultraflex contact:
Multichem Industries Pvt. Ltd.
Phone No: +91 9619091025
E-mail: info@multichemgroup.net
Web: www.multichemgroup.net