Hydraulic lime mortars with antifungal properties

Abstract

The use of lime-based coatings came into disuse with the appearance of cement, a stronger and easier to apply binder. However, cement mortars have proven to be rigid to replace lime mortars. In rehabilitation the use of lime-based mortars has been more frequent. With the increase of this type of works it is expected to increase the application of this type of coatings. Fungi develop on the surface, inside pores and cracks of walls and ceilings and they play a very important role in the degradation of the quality of the buildings and their interior environment. Inside the buildings, the growth of fungi in wet areas, in addition to hygiene and aesthetic problems can also cause respiratory allergy problems. This study aimed to develop hydraulic lime mortar incorporating nano additives with antifungal properties. The main objective of this study was to verify the development of fungi in mortars added with nano TiO2. The physical and mechanical characteristics were also verified. For this, four different compositions were developed. The amount of nano TiO2 was varied. It has been possible to observe that the incorporation of nano TiO2 causes significant differences in properties such as workability, compressive and flexural strength. Some changes observed in the mortars were compensated by varying the dosage of the superplasticizer. The antifungal properties of nano additivated mortars with TiO2 were verified. The results obtained could be a starting point for a transition from the current antifungal protections to new antifungal protections using nano additives. This transition of antifungal protection will allow an improvement of the quality of the constructions, the health of the users as well as the environmental quality.