Composite Hydrophobic Coatings with Progressive High Penetration through Chromatography: Protective Properties and Mechanisms

Hydrophobic treatment is one of the common measures to improve the durability of concrete. It enhances the durability of the concrete by establishing a hydrophobic barrier. However, the hydrophobic treatments commonly found in the market have a limited impact on the pore structure of the concrete surface. As a result, the concrete remains vulnerable to erosion caused by carbon dioxide and gaseous water. This paper presents a compound silane treatment agent that ensures good water repellency and improves the pore structure of the concrete surface. It has advantages over silane monomers in resisting water vapor and carbon dioxide migration. The pore refining mechanism of the compound silane was investigated using XRD and TG test methods. According to the results of the FTIR analysis, the compound silane penetrated the concrete in the form of a gradient. Compound silane can both repel water and refine pores. They are useful for addressing mold and peeling that result from water vapor on the surface layer.