Page 119 - Construction Waterproofing Handbook

3.8 CHAPTER THREE

FIGURE 3.2 Repellency of sealer application. (Courtesy of Saver Systems)

TABLE 3.2 Repellent Types and Compositions
Penetrating sealers Film-forming sealers
Siloxanes Acrylics
Silanes Silicones
Silicone Rubber Aliphatic urethane
Siliconates Aromatic urethane
Epoxy-modified siloxane Silicone resin
Silane–siloxane combination Methyl methacrylate
Siloxane–acrylic combination Modified stearate

Film-forming sealers
Film-forming, or surface, sealers have a viscosity sufficient to remain primarily on top of
a substrate surface. Penetrating sealers have sufficiently low viscosity of the vehicle
(binder and solvent) to penetrate into masonry substrate pores. The resin molecule sizes of
a sealer determine the average depth of penetration into a substrate.
Effectiveness of film-forming and penetrating sealers is based upon the percentage of
solids in the material. High-solid acrylics will form better films on substrates by filling
open pores and fissures and repelling a greater percentage of water. Higher-solids-content
materials are necessary when used with very porous substrates; however, these materials
may darken or impart a glossy, high sheen appearance to a substrate.