A University of Washington study has shown that used surgical masks can make concrete stronger and more durable.
Reusing surgical masks to produce concrete is good for the environment.
One of the first problems during the outbreak of the pandemic was the omnipresence of surgical masks, essential but difficult to re-use protective devices.
Now, a University of Washington study has shown that it’s possible to incorporate them into a cement mix to create a stronger, more durable material.
Research shows that the mixture produced by reusing the masks is 47% stronger than commonly used cement.
This waste could actually be a valuable asset if handled properly.
Xianming Shi, professor in the Department of Civil and Environmental Engineering.
Cement production is a process that accounts for 8% of carbon emissions worldwide. However, microfiber-reinforced concrete can reduce the amount of cement needed, which reduces emissions. The addition of microfibers also makes the material stronger and lasts longer. The problem, however, is the cost of the process, which could be reduced by the very idea of reusing the masks.
Indeed, the devices that we have been transporting for a few years are made of polypropylene or polyester, ideal materials for the concrete industry.
Innovation could have multiple benefits: the reuse of the masks would avoid their abandonment in the environment, where they could remain for decades with all the possible risks for the ecosystems.
This work shows a technology to divert used masks from the waste stream to a high value-added application.
Practical application and future prospects.
The fibers of reusable masks range from 5 to 30 mm. When added to cement, they help prevent cracking.
For the experiment, the scientists removed the cotton and metal parts from the insoles, then embedded the remaining material in Portland cement, the most common cement in the world. The microfibers were first mixed with a graphene oxide solution and then added to the cement paste.
Graphene oxide is used to provide ultra-thin layers that adhere perfectly to fiber surfaces. In this way, the microfibers of the soles are able to absorb the energy and the impact often created by the large and small fractures of the concrete until the material degrades.
The aim is to apply this recycling technology also to other discarded polymer materials, such as textile fibres. This would amount to contributing to closing the loop of this type of waste.
Going through wsu.edu