On the role of hydrophobic Si-based protective coatings in limiting mortar deterioration

摘要: In order to avoid both natural and artificial stone decay, mainly due the interaction with atmospheric pollutants (both gases such as NOx SO2 particulate matter), polymeric materials have been widely studied protective coatings enable limit penetration of fluids into bulk material. current work, an air hardening calcic lime mortar (ALM) a hydraulic (HLM) were used substrates, commercially available Si-based resins (Alpha®SI30 Silres®BS16) adopted agents give hydrophobicity features stones. Surface properties their performance hydrophobic using different techniques contact angle measurements, capillary absorption test, mercury intrusion porosimetry, surface free energy, colorimetric measurements water vapour permeability tests. Finally, some exposure tests UV radiation real polluted environments (a city centre urban background site) carried out during wintertime period (when concentrations main are higher) in study durability coating systems applied. The effectiveness two commercial reducing salt formation (sulphate nitrate), induced by mortars pollutants, was demonstrated case HLM mortar.