In recent years, research projects on coating and strengthening products for the protection and conservation of building stones has been increased. In particular, cheap, eco-friendly, reversible, compatible and high activity products are under testing in order to verify their efficiency and applicability on stones. In this work we present the results obtained on the Sabucina Stone, a calcarenite outcropping in Central Sicily and widely used as building and replaced stone, by applying TiO2 nanoparticle coatings and hybrid organic-inorganic strengthening products. The durability of the studied calcarenite determined by its structural, textural and porosimetric features, requires an integrated preservation and conservation of stone both in terms of surface protection and structural strengthening. First we tested self-cleaning photocatalytic coatings based on TiO2 nanoparticles obtained by the sol-gel process at different pH values. Photocatalytic activity of theTiO2 coatings on Sabucina Stone was assessed under daylight and ultraviolet irradiation, monitoring methyl orange (MeO) and methyl blue (MB) dye degradation as a function of time. To evaluate the effect of the treatment, colorimetric and water absorption tests were performed. Moreover, in order to verify the action of coating in inhibiting degradation processes, aging tests were carried out by evaluating stone resistance to salt crystallization. Second, a network based on aluminium and silicon oxides with epoxidic functional groups have been used with strengthening aims. In order to test the effectiveness of the hybrid organic-inorganic strengthening product, colorimetric, water adsorption, compressive strength and aging tests have been performed. Finally, the performance of a hydrophobic coating applied in association with the strengthener was verified by colorimetric and water adsorption tests. The results obtained show good photodegradation rates for titania nanosols and good protection properties, especially using the basic pH preparation. With reference to hybrid organic-inorganic strengthening products and hydrophobic coatings, preliminary tests highlight promising applications to the preservation of calcarenites.
Self-cleaning photocatalytic coating and hybrid organic-inorganic strengthen products for the protection and conservation of calcarenites from Sabucina (Italy, Sicily)
RANERI, SIMONA;
2014-01-01
Abstract
In recent years, research projects on coating and strengthening products for the protection and conservation of building stones has been increased. In particular, cheap, eco-friendly, reversible, compatible and high activity products are under testing in order to verify their efficiency and applicability on stones. In this work we present the results obtained on the Sabucina Stone, a calcarenite outcropping in Central Sicily and widely used as building and replaced stone, by applying TiO2 nanoparticle coatings and hybrid organic-inorganic strengthening products. The durability of the studied calcarenite determined by its structural, textural and porosimetric features, requires an integrated preservation and conservation of stone both in terms of surface protection and structural strengthening. First we tested self-cleaning photocatalytic coatings based on TiO2 nanoparticles obtained by the sol-gel process at different pH values. Photocatalytic activity of theTiO2 coatings on Sabucina Stone was assessed under daylight and ultraviolet irradiation, monitoring methyl orange (MeO) and methyl blue (MB) dye degradation as a function of time. To evaluate the effect of the treatment, colorimetric and water absorption tests were performed. Moreover, in order to verify the action of coating in inhibiting degradation processes, aging tests were carried out by evaluating stone resistance to salt crystallization. Second, a network based on aluminium and silicon oxides with epoxidic functional groups have been used with strengthening aims. In order to test the effectiveness of the hybrid organic-inorganic strengthening product, colorimetric, water adsorption, compressive strength and aging tests have been performed. Finally, the performance of a hydrophobic coating applied in association with the strengthener was verified by colorimetric and water adsorption tests. The results obtained show good photodegradation rates for titania nanosols and good protection properties, especially using the basic pH preparation. With reference to hybrid organic-inorganic strengthening products and hydrophobic coatings, preliminary tests highlight promising applications to the preservation of calcarenites.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
