Simple preparation of superhydrophobic montmorillonite mortar for enhancing corrosion resistance while maintaining flexural strength

Marine structures are susceptible to chloride ion erosion due to being exposed to high salt and high humidity environments for a long time, leading to deterioration of their durability. Despite the corrosion resistant potential of superhydrophobic mortars, existing preparation methods suffer from complex processes and insufficient flexural strength. Here, a simple method for preparing superhydrophobic montmorillonite mortar (SMM) was developed by ball milling modified montmorillonite (MMT) combined with sanding. The prepared mortar has a water contact angle (WCA) of ∼151° and a water sliding angle (WSA) of ∼6°, showing excellent superhydrophobicity. The SMM was tested for water absorption, and its water absorption was only 1.56 % after 102 h of immersion in water, showing good waterproof performance. Electrochemical tests after 28 d of immersion in 3.5 wt% NaCl solution showed a low corrosion current and high potential. There was no corrosion of its internal reinforcing steel, showing excellent corrosion resistance performance. Notably, the flexural strength of the SMM was reduced by only 1.83 % compared with that of the ordinary mortar. The prepared SMM has good corrosion resistance while maintaining high flexural strength, which is expected to be applied in floating concrete structures in marine environments. • Superhydrophobic montmorillonite mortar was prepared by a simple ball milling method. • Superhydrophobicity and waterproof performance were exhibited. • Corrosion resistance performance was displayed after 28 d of immersion in 3.5 wt% NaCl solution. • The flexural strength of the prepared mortar was reduced by only 1.83 % compared with the ordinary mortar.