Design of Impermeability and Durability for Superhydrophobic Mortar

The ubiquitous use of mortar in construction is compromised by its susceptibility to environmental degradation, including water penetration, abrasion, and UV radiation, which significantly reduce its service life. To address these challenges, a new type of superhydrophobic mortar with a water contact angle of 155° and a sliding angle of 8° (SC-4) was fabricated by using the method of propriety hydrophobic modification. The compressive strength (CS) of SC-4 was 29.83 ± 1.2 MPa, and the flexural strength (FS) was 5.47 ± 0.3 MPa at the age of 28 days, showing balanced mechanical properties. Compared to the ordinary mortar (OC) group, SC-4 maintained competitive interfacial wettability. Notably, despite 25% lower compressive strength than the benchmark, SC-4 exhibited enhanced structural stability through optimized integration. Leaching tests validated its outstanding impermeability with significantly reduced cumulative water and NaCl absorption. After 200 abrasion cycles, it maintained superhydrophobicity and minimal mechanical property variation, while UV aging tests showed only marginal strength degradation, confirming robust resistance to environmental stressors. This study highlights SC-4's superior impermeability and durability, offering a practical solution for mortar applications.