Researchers in Germany are set to turn green waste, hay and algae into fully biodegradable plastics. They believe such plastics can be used in medical products, car components, insulation and packaging.
The plan is to develop a cost-effective, energy-efficient technology for making innovative plastics based on polybutylene succinate (PBS) which are made entirely out of organic waste.
A new Junior Research Group at the University of Oldenburg plans to develop this method.
PBS resembles the conventional plastics
“The work of the new Junior Research Group aims to offer plastics made from renewable raw materials as an industrially viable alternative to conventional plastics,” said Prof. Dr. Ralph Bruder, President of the University of Oldenburg.
“The BMFTR’s funding approval also acknowledges our university’s outstanding research infrastructure in this field and highlights the potential of EcoPBS in creating an environmentally and climate-friendly circular economy.”
Researchers revealed that PBS resembles the conventional plastics polypropylene and polyethylene in terms of robustness and processability, with the major advantage of being readily biodegradable. However, scientists have yet to produce an entirely bio-based material that is fully recyclable, and the manufacturing processes are not yet suitable for use in the chemical industry.
Stable enough to be efficient in low-cost, low-energy processes
“For a high yield, you need microorganisms that are easy to grow and stable enough to be efficient in low-cost, low-energy processes,” said Walther.
In three sub-projects, the Junior Research Group will therefore investigate how to turn a biological substrate consisting of garden cuttings and crop waste into Bio-PBS. The team’s first step will be to optimise the fermentation process: in a newly developed biotechnological process they will assess how effectively the organic material can be converted into bioplastics using different types of microorganisms. A key factor here is that two different fermentation processes – Acetone-Butanol-Ethanol (ABE) fermentation and succinic acid fermentation – will be tested, according to the details available.
It has also been revealed that the second sub-project will focus on “downstreaming” – the process of removing foreign substances from the converted material. The goal here is to convert the organic compound n-butanol into 1,4 butanediol, a bivalent alcohol and important raw material for plastics. With the help of simulations and machine learning they will look for ways to improve the material and energy balances of this process.
It was also highlighted that a new chemical substance is needed to remove contaminants and thus produce the first fully biodegradable BPS. The team has already developed a basic blueprint for this substance and applied for a patent. In the third sub-project it plans to further refine the technology. Another goal is to use the residues from the production of bio-PBS to generate renewable electricity and heat that can be used to operate the laboratory facilities. In the final step, the researchers aim to manufacture the first products for industrial use – for example, packaging and medical materials – using digital 3D models and fully bio-based PBS, as per the release.