Single-use masks could strengthen concrete

Published in Materials Letters, a team at Washington State University demonstrated that using waste materials from disposable masks could improve the mixture’s strength by 47 per cent, compared with commonly used cement after a month of curing.

“These waste masks actually could be a valuable commodity if you process them properly,” said co-author Xianming Shi, professor and interim chair of the Department of Civil and Environmental Engineering. “I’m always looking out for waste streams, and my first reaction is ‘how do I turn that into something usable in concrete or asphalt?’”

Cement production is responsible for as much as eight per cent of worldwide carbon emissions. Microfibres are sometimes added to cement concrete to strengthen it, but are expensive. Microfibre-reinforced concrete can potentially reduce the amount of cement needed for a project or make the concrete last longer, reducing both cost and emissions.

Made of a polypropylene or polyester fabric where it contacts the skin and an ultra-fine polypropylene fibre for the filtering layers, medical masks’ fibres can be useful for the industry, researchers said. If not reused, disposable masks can remain in the environment for decades.