Solvent-Free Sealant From Bayer Materialscience Creates Smooth Concrete Surface For Coating

Pittsburgh, PA - One of the galling glitches of hardened concrete structures is the "bughole," a small hollow caused by a bubble of air trapped against the side of the support form as the concrete hardens, leaving a permanent void in the finished surface. Bugholes pose a significant problem when applying high-performance coatings to concrete surfaces, and need to be filled in order to achieve a smooth finished coating. Desmoseal S XP 2636 silane-terminated polyurethane prepolymer by Bayer MaterialScience (BMS) LLC is used as a base resin in a solvent-free, one component sealant ideal for eliminating bugholes in concrete surfaces.

To eliminate bugholes before a high-performance coating is applied to a concrete substrate, a simple caulking gun is used to inject a formulated product based on a Desmoseal resin into a void. The uncured product is then pulled flush with a putty knife, creating a smooth surface ready for coating. This process eliminates the risk of bughole-induced outgassing through the post-applied coating. Outgassing occurs when air becomes entrapped within the cavities and expands over time from the heat of an exothermic coating, thereby causing pinholes, blisters or other defects in the finished surface.

Desmoseal S XP 2636, a silane-terminated prepolymer, is part of a new class of materials that cure with moisture from the air, or from the substrate to which they are applied. The finished products will not foam in the presence of water, and have excellent UV stability and good adhesion to concrete. The products also have very fast re-coat time and can be formulated without solvents.

"Desmoseal S XP 2636 resin is part of our proven portfolio of trusted raw materials formulations," said Jay Johnston, senior associate scientist, Adhesives and Sealants, BMS LLC. "Desmoseal resin formulations result in finished products that cure reliably without bubbles or blisters."

Desmoseal resin-derived sealants can be used on any concrete surface that has been poured into a mold. Common applications include concrete basement and retaining walls.

SOURCE: Bayer MaterialScience LLC