Upcycling nanocomposites from discarded face masks may help reduce global pollution problem

Once essential for curbing the spread of COVID-19, disposable face masks have become a major contributor to environmental pollution and human health concerns.

Over the past four years, more than 950 billion masks—equivalent to about 3.8 million metric tons—have been discarded worldwide. Most end up in landfills or are incinerated. These masks take centuries to decompose, posing a major threat to wildlife and agricultural production.

Researchers from the University of Southern Queensland (UniSQ), in collaboration with colleagues in China, have proposed a cost-effective upcycling strategy that offers promising environmental and economic benefits. The team developed a new technique to extend the life of polypropylene materials from discarded masks by breaking them down and repurposing them into valuable components for use in electronic devices such as smartphones and LED lights.

The work, published in Nano-Micro Letters and titled “Highly Thermal Conductive and Electromagnetic Shielding Polymer Nanocomposites from Waste Masks,” was co-authored by UniSQ’s Professor Polly Burey and researchers from Beijing Forestry University, Nanjing Forestry University, and Beijing University of Chemical Technology.

Senior researcher and co-author Professor Pingan Song said the innovation could significantly reduce the environmental impact of disposable masks.

“Incinerating waste masks releases toxic gases such as dioxins and furans, causing air pollution, while landfilled masks not only take hundreds of years to degrade fully, but often generate large amounts of microplastics that cause long-term pollution of water sources, soil and food chains,” Professor Song said.

“Single-use face masks—most of which are not recyclable—remain widely used, especially in laboratories, hospitals and other health care settings. Without more public awareness and a sustainable management solution to manage the high volume of waste masks that are still generated every day, they will continue to exacerbate the ongoing pollution crisis.”

The research team investigated the thermal conductivity and electromagnetic interference (EMI) shielding properties of nanocomposites derived from recycled polypropylene-based waste masks, utilizing a surface treatment and hot-pressing process that converts the masks into functional films.

The study found that the regenerated nanocomposites exhibit metal-like thermal conductivity and effective EMI shielding, offering the potential to help cool electronic devices and shield against electromagnetic signals.

“This research presents a novel upcycling method that tackles pollution from discarded masks while converting them into low-cost yet high-value nanocomposite products,” Professor Song said. “It offers industries an affordable, high-performance solution for developing advanced heat dissipation and electromagnetic shielding materials and opens new economic opportunities in electronics and recycling.”

Professor Song said the team intends to collaborate with industry to develop more value-added products, such as heat sinks for chips and electronic devices. They also aim to convert waste masks into high-value carbon nanomaterials within the next three years.

Professor Song also urged governments to introduce a recycling program to reduce the number of disposable masks in landfills and to mitigate their environmental impacts.