Assessment and mechanism of inorganic hydrophobic flake incorporated into a polymer-modified cement-based coating

Due to internal defects, the traditional polymer-modified cement-based coating was hard to meet the high durability requirement of construction engineering. The hydrophobic flake as a functional filler provided a new solution for improving the protection performance. However, there has been almost no application report in this system so far. In this study, we tried to obtain the optimal number and mechanism by studying the effect of hydrophobic flake on the mechanical, waterproof, and brine soaking resistance properties of the coating with calcium sulphoaluminate (CSA) cement and polyacrylate (PA) emulsion as the main components. The results showed that the unique irregular tight structure of the hydrophobic flake would not only make the internal coating rougher and denser but also cut off the transport paths of harmful molecules inside the coating. The hydrophobic flake was beneficial to the mechanical properties and the brine soaking resistance of the polymer-modified cement-based coating.