A group of researchers at the National University of Singapore, none of whom would be welcome in Donald Trump’s America, have created an inexpensive way to convert plastic bottles into a lightweight aerogel that has some extraordinary properties.
Plastic waste is a scourge that is burdening landfills and polluting the world’s oceans. Most plastic bottles are made from polyethylene terephthalate — commonly known as PET — which is non-biodegradable. The problem is that the single use bottles have virtually no commercial value after the products inside are consumed, so they are simply discarded.
The researchers have found a way to take those unwanted and unloved bottles and convert them into aerogels. They are still discovering some of the things the aerogels can be used for, but already know that when treated with fire retardants, they can be used to protect firefighters from flames and intense heat.
In fact, the aerogels can withstand temperatures of up to 620 degrees Celsius. That is seven times higher than the thermal lining used in conventional coats for firefighters. It also weighs 90% less than the material used today. Because it is soft and flexible, the improved coats are also more comfortable to wear.
Each recycled bottle can produce a sheet of aerogel about the size of a normal piece of paper. Cut that sheet and insert it into a normal respirator or protective mask and it not only does a better job of cleaning pollutants from the air we breath, it removes carbon dioxide and carbon monoxide as well.
“Masks lined with amine-reinforced PET aerogels can also benefit people living in countries such as China, where air pollution and carbon emission are major concerns. Such masks can be easily produced, and can also potentially be made reusable,” says associate professor Hai Minh Duong. The researchers make no grandiose claims about using the material for large scale carbon capture, but the implications are intriguing.
“Plastic bottle waste is one of the most common type of plastic waste and has detrimental effects on the environment. Our team has developed a simple, cost-effective and green method to convert plastic bottle waste into PET aerogels for many exciting uses. One plastic bottle can be recycled to produce an A4-sized PET aerogel sheet. The fabrication technology is also easily scalable for mass production. In this way, we can help cut down the harmful environmental damage caused by plastic waste,” says Duong.
The aerogel also has superior sound and thermal insulation properties. Using it in the walls of buildings could dramatically reduce the energy needed for heating and cooling while making the space inside more pleasant to live and work in.
Another potential use is soaking up oil and chemical spills. “Our PET aerogels are very versatile. We can give them different surface treatments to customise them for different applications. For instance, when incorporated with various methyl groups, the PET aerogels can absorb large amounts of oil very quickly. Based on our experiments, they perform up to seven times better than existing commercial sorbents, and are highly suitable for oil spill cleaning,” says professor Nhan Phan-Thien.
The research team is now focusing on finding commercial manufacturing partners, according to a report by Science Daily. If this research creates a viable market for discarded single use plastic bottles, that would go a long way toward reducing the burden plastic waste imposes on the environment.