Silicone-based water repellents: new developments and new applications

 
Protecting inorganic porous construction material against water absorption is key to prevent water-induced degradation phenomena such as freeze thaw damages, efflorescence or steel bar corrosion. Application of film forming coatings, made of acrylic polymer dispersion as well as silicone-based impregnation water repellents are well known methods, used to protect porous inorganic construction materials. But acrylic dispersion can lead to the surface appearance modification and silicone based water repellent is sometime not effective enough to prevent efflorescence on cement-based substrate. This paper will explore the benefit of combining silicone and acrylic technology to protect porous inorganic construction materials. Silicone impregnation can be formulated with film forming acrylic polymer dispersion for achieving unmodified surface appearance with improved protection against water induced phenomena such as efflorescence. Impact of acrylic polymer composition and silicone components (silane vs polydimethylsiloxane vs silicone resin) on the mixture and film formation will be shared.