Researchers from the University of Birmingham and Duke University have developed a sugar-based plastic. Their https://pubs.acs.org/doi/10.1021/jacs.1c10278.
The researchers developed two types of materials: one that is similar to rubber, and another that is tough but pliable like many plastics used in everyday life. The sustainable plastics’ performance is equal or superior to that of commonly available plastics, while also being degradable and easy to recycle. Different from other recyclable plastics, their mechanical properties are not affected after being reprocessed.
As an alternative to petroleum plastics, biodegradable plastics made from renewable plant sources like corn or sugarcane starch are already on the market and becoming popular. However, they typically biodegrade only in industrial compost facilities and they need to be recycled separately from other plastics.
The mechanical properties of known sustainable plastics also don’t match those of commercially available plastics, says Matthew Becker, a chemistry professor at Duke University, who led the new work with University of Birmingham, UK chemistry professor Andrew Dove. “Many others have used sugar and sustainably sourced feedstocks to synthesize materials,” he says. “However, the properties are often poor and therefore not useful in commercial application.”
The researchers made two different organic compounds from sugar alcohols, and used them as the building blocks for their plastics. The two compounds contain ring-like structures made of the same atoms, but their properties differ based on how the atoms are arranged relative to each other.
According to the study, “plastic made from one of the compounds is as stiff yet malleable as common plastics, and about as strong as high-tech plastics such as Nylon-6. The other compound gives plastics that are just as strong but also has elastic properties that are better than known rubbers”.
Both materials seemed to maintain these properties after they were heated and reformed using the typical commercial recycling process for plastics. Preliminary tests in the lab also showed that the new plastics should be able to degrade, albeit slowly, if they were released into the environment.
“The mechanical and degradation properties exhibited by the materials are tunable, which will be important to many of the applications we are targeting,” Becker says. “These materials could be applied to a number of replacement applications including food packaging.”