With plastic waste piling up, efforts are concentrated to reduce use of plastics and ban single use items. At the same time, new developments appear in the front of recycling existing waste. Researchers from the National University of Singapore and the Singapore Institute of Manufacturing Technology have developed a procedure to convert polyethylene terephthalate (PET) bottles into aerogels. PET is turned into fibers which are in turn treated chemically to form porous, lightweight materials.
These materials have excellent insulation and absorption properties and a potential for multiple applications. They can be used as lining for fire-retardant coats for fire-fighters, as insulation material for buildings (or even in space exploration, as in the case of the Mars Pathfinder rover) and they could even be used to clean oil spills.
For the latter, the researchers found that their PET-derived, methyl-coated aerogel can absorb up to seven times more oil than commercial sorbents, thanks to its water-repellent properties. Similarly, the aerogel can be coated with different chemicals that alter their properties. For example, with flame retardant coatings, the aerogel becomes seven times more fireproof and lighter than conventional fireproof linings.
An amine coating allows the aerogel to absorb toxic gases and makes it a good component for the production of face masks. On top of their diverse applications, PET-based aerogels are manufactured following a procedure which is now faster and considerably cheaper than common commercially available alternatives.
The team is further working on other aerogels. Having already pioneered the construction of aerogels from cellulose (from paper waste) and from cotton waste, they extend now to rubber waste, and are setting up a company to bring their aerogels in the market.