The new polyester-2.18 is a biodegradable plastic created by the University of Constance
(sustainabilityenvironment.com) – A few months or even days to degrade: the new biodegradable plastic created by the chemistry laboratories of the University of Constance combines the physical characteristics that guarantee the strength of the material with environmental sustainability.
The pervasive diffusion of plastic in the past decades was essentially due to its extreme durability, ideal to withstand time and at the same time have reduced costs. However, it is these characteristics that have created a pollution problem.
A product made of plastic is extremely versatile and resistant to external conditions, including water and heat, but these same qualities become critical when its end of life arrives, which turns it into a waste. Plastic waste remains in the environment, stored in landfills or in our oceans and is destined to last for thousands of years.
The extreme resistance of the most widespread plastic also generates a secondary problem, connected to the end of life: even recycling it is very difficult, due to the hardness of the bonds that characterize it.
Biodegradable plastic in a few days
The characteristics of extreme durability of plastic are engaging the field of research in the design of materials. The goal is to identify a type of plastic that is biodegradable in a significantly reduced time, while maintaining the same strength characteristics.
It is the goal that seems to have reached a group of chemists from the University of Constance, whose results have been published in the journal Angewandte Chemie.
The new polyester-2.18 consists of two modules, a glycol composed of two carbon atoms and a dicarboxylic acid of 18 carbon atoms. However, chemists have made the material with specific “breaking points“, which in certain conditions bring biodegradable plastic back to the two basic modules in a short time. So as to ensure recovery and reuse, while maintaining the physical characteristics associated with the dense crystalline structure.
The material also has an additional potential advantage, because the basic modules can be obtained from renewable sources.
The new biodegradable plastic has already passed two tests in the laboratory. In the first case, it was tested with natural enzymes and degraded within a few days. The second experiment was conducted in an industrial composting plant and through the use of other microbes. In this case, the material decomposed in about two months, a record time compared to the dissolution of standard plastics.
“We were also amazed by this rapid degradation,” said Stefan Mecking, author of the study. “Of course we cannot transfer the results of the composting plant to any environmental condition imaginable. But they confirm that this material is actually biodegradable and indicate that it is much less persistent than plastics such as high-intensity polyethylene, should it inadvertently be released into the environment”.