Scientists at Swiss Federal Institute of Technology Lausanne (EPFL) have developed a new, PET-like plastic that is made from non-edible parts of plants. EPFL says the plastic is tough, heat-resistant, and a good barrier to gases like oxygen, making it potentially useful for food packaging. The new plastic can be chemically recycled and degrade back to sugars in the environment.
Professor Jeremy Luterbacher at EPFL’s School of Basic Sciences have successfully developed a biomass-derived plastic,
“We essentially just ‘cook’ wood or other non-edible plant material, such as agricultural wastes, in inexpensive chemicals to produce the plastic precursor in one step,” said Professor Jeremy Luterbacher, who led the team that developed the biomass-derived plastic.
“By keeping the sugar structure intact within the molecular structure of the plastic, the chemistry is much simpler than current alternatives.”
The technique is based on a discovery that Luterbacher and his colleagues published in 2016, where adding an aldehyde could stabilize certain fractions of plant material and avoid their destruction during extraction. By repurposing this chemistry, the researchers were able to rebuild a new useful bio-based chemical as a plastic precursor.
“By using a different aldehyde – glyoxylic acid instead of formaldehyde – we could simply clip ‘sticky’ groups onto both sides of the sugar molecules, which then allows them to act as plastic building blocks,” says Lorenz Manker, the study’s first author. “By using this simple technique, we are able to convert up to 25% of the weight of agricultural waste, or 95% of purified sugar, into plastic.”
The properties of these plastics could allow them to be used in applications ranging from packaging and textiles to medicine and electronics. The researchers have already made packaging films, fibers that could be spun into clothing or other textiles, and filaments for 3D-printing.
“The plastic has very exciting properties, notably for applications like food packaging,” says Luterbacher. “And what makes the plastic unique is the presence of the intact sugar structure. This makes it incredibly easy to make because you don’t have to modify what nature gives you, and simple to degrade because it can go back to a molecule that is already abundant in nature.”
Image credit: Lorenz Manker