Valorisation of face mask waste in mortar

In view of the COVID-19 pandemic, most countries in the world have mandated the use of face masks to limit the spread of this dangerous disease. The billions of face masks that are produced around the world to date generate millions of tonnes of plastic waste that is thrown into the environment. The present work aims to valorise single-use masks or surgical masks in mortar. In this work, the effect of substituting 1–5% of the volume of the mortar with pieces of masks of 2 cm(2) section and 4 cm(2) section is explored. Mechanically, an increase in compressive strength of between 10 and 20% is noted, as well as an improvement in flexural strength of 19–30%. Physically, the thermal resistance of the mortars formulated from waste mask improved by up to 23%, and there was a clear improvement in the acoustic reflection coefficient for all frequencies. The capillary rise test conducted on the mortar samples shows that the amount of the absorbed water increases. However, although in most cases the presence of mask pieces increases the sorptivity of the mortar, this is not associated with a higher capillary rise. The results found are encouraging, allowing on the one hand to improve the physical and mechanical characteristics of the mortar and on the other hand to solve a dangerous environmental problem.