MASCO Catalog: Construction Liquid and Powder

49 MASONS SUPPLY COMPANY Oregon (800) 537-3407 ♦ Washington (800) 537-6216 ♦ www.MASCO.net Clackamas | Eugene | West Eugene | Hillsboro | Medford | Portland | Salem | Ridgefield | Seattle | Tacoma | Woodinville Concrete sealers are being used with increasing frequency in both exterior and interior applications. When designed for use in exterior applications, the primary function of a concrete sealer is to protect concrete from freeze/thaw damage and chloride induced corrosion of the reinforcing steel. For interior use, concrete sealers are applied to floor slabs to prevent dusting and absorption of liquid spills, and to make the surface easier to clean. The sealer products available today may be classified as either film-forming or penetrating. With film-forming sealers, penetration of durable concrete will be slight at best, with most of the product remaining on the surface to form a barrier. The ability of theses products to effectively penetrate concrete is restricted by the relatively large molecular structure of the materials. The use of solvents, therefore, will not appreciably enhance penetration capabilities. In addition to sealing out water, these products also offer some protection against mild chemicals and prevent the absorption of grease, some oils and other liquid spills. Film-forming sealers will substantially reduce dusting under light traffic conditions. Re treatment intervals are highly variable depending on traffic and exposure. Urethanes and epoxies are two of the most commonly used film-forming sealers. In general, urethanes typically demonstrate greater abrasion resistance while epoxy sealers have shown superior chemical resistance. The effectiveness of penetrating sealers is a result of their very small molecular size in comparison with urethanes or epoxies. These materials are able to infiltrate and coat the pores and capillary structure of concrete. Penetrating sealers may achieve penetration depths of as much as 1/8 in., depending on the density and finish of the concrete. Unlike film-forming sealers, the effectiveness of penetrants is not dependent upon the continuity of an exposed surface film. Penetrants produce a durable sealing film embedded within the concrete itself that is reactively unaffected by abrasion or ultraviolet-induced deterioration. The two most common penetrating sealers, the silanes and the siloxanes, are both derived from the silicone family. When catalyzed by moisture, these silicon materials react with silica available in concrete to form an interstitial, hydrophobic siloxane resin film that repels water without loss of vapor transmission properties. Despite being very closely related, the two silicone-based materials have significant performance differences. Silane monomers are small molecules which have not yet reacted with other similar molecules to form polymer chains and require a substrate with a high pH. Siloxanes are produced when silane molecules are partially reacted to form a larger structure linking up two or three silane molecules and are not dependent on substrate pH. Because of this, siloxanes are ideal for treating brick, stucco and stone. Because of their very small molecular size, silanes will typically obtain deeper penetration and as a result are less subject to loss of effectiveness caused by abrasion or weathering. A consequence, however, of this very small molecular size is that the molecule is relatively volatile. The solids content in a finished silane product should be high enough to compensate for the loss of reactive material through evaporation during application and cure. Siloxanes, because they are less volatile, generally offer good hydrophobic performance at lower initial cost than do silanes. However, for concrete surfaces subject to abrasive wear such as pavements and decks, treatment with a silane sealer will provide longer-lasting protection. In regard to surface texture and color, treatment with silane sealers typically cannot be visually detected. Siloxane products may slightly darken the treated surfaces. Liquid hardeners contain inorganic compounds that undergo a series of complex chemical reactions with the available lime in mature concrete. They also contain special proprietary ingredients to make treated floors more resistant to chemical attack and wear and to improve the aesthetics of the finished surface. Liquid hardeners are water soluble and comply with today’s environmental concerns. Wetting agents are added to a liquid hardener to help the product penetrate the pores of the concrete substrate. The effectiveness of the treatment increase with the depth of penetration, typically from 1/8 to ¼”. The surface is protected down to the depth of penetration. The hardeners do not form a surface membrane, so they do not peel, rubber tire burn or require recoating. As soon as the liquid hardener is applied a chemical reaction take place between the inorganic compounds of the hardener and lime in the pore of the concrete matrix. The reaction of silicate compounds and water produce a calcium silicate hydrate or tobermorite gel, already a primary binding property of hydrated portland cement. Liquid hardeners increase the concentration of tobermorite gel which increases the density, hardness and chemical resistance. The floor finish is enhanced by giving the floor a more polished look. A high sheen results when the treated floor is polished by mechanical means. Concrete floors should be at least 7 to 14 days old before treatment because the concrete needs sufficient time to hydrate. Hydration increases the amount of lime available to react and form the tobermorite gel. In addition the waiting time allows the pores of dry so the hardener can penetrate deeper. Liquid floor hardeners are recommended for industrial and commercial floors, although they are not a direct replacement for a dry shake floor hardener. Consult Masons Supply for more information on which product should be used for your specific application. Film Forming-Sealers Penetrating Sealers Liquid Hardeners SEALING/HARDENING COMPOUND GUIDE Sealing/Hardening Compounds