摘要 |
<p>The invention provides a water repellent composition for treating porous substrates comprising an emulsion which includes water, at least one surfactant, and a siloxane copolymer having the formula (I) wherein R is an alkyl radical having 1 to 3 carbon atoms; a has a value of from 1 to 12; R′is an alkyl radical having 8 to 12 carbon atoms, b≧2; (a+b) is at least 5. This composition shows a good depth of penetration of porous substrates especially reinforced concrete and has a low Volatile Organic Content to ASTM D 5095.</p> |