Heat-Resistant Above 200°C, Germany Develops New Bio-Based PBS Plastic for Industrial Applications

For many years, bioplastics have been the focus of efforts to find environmentally friendly alternatives to traditional plastics. They can reduce the demand for fossil resources, conserve materials, and help lower carbon dioxide emissions. However, for industrial applications, bioplastics need to be not only sustainable but also easy to process. This is precisely the direction being pursued by the Fraunhofer Institute for Applied Polymer Research (Fraunhofer IAP), located in the Potsdam Science Park. The institute will showcase its latest achievements in the field of bio-based and biodegradable plastics at the International Trade Fair for Plastics and Rubber (K 2025) in 2025.

As part of the RUBIO project, an entrepreneurial alliance for the development of a value chain for technical bioplastics in central Germany, researchers have successfully developed around 20 new types of polybutylene succinate (PBS) plastics and completed pilot-scale production and processing. Injection molding, deep drawing, extrusion, and spinning—these new types of PBS, which can be made from plant residues, are adaptable to various processing methods and can be widely used in packaging, consumer goods, and textiles.

From Laboratory to Production

Researchers at Fraunhofer IAP have scaled up the synthesis of PBS from laboratory scale to 100 kilograms. To date, they have produced a total of about 3 tons of PBS. By altering the synthesis parameters, the researchers have obtained PBS with different properties. Among them, three models with differentiated flow characteristics have been developed specifically for injection molding processes; other types of PBS are suitable for blow molding, thermoforming, blown film or sheet extrusion processes, as well as meltblown or spunbond nonwovens. The polymer structure has a decisive influence on processing performance. Depending on the processing method, the molecular chains must be designed with differentiated structures. The researchers have successfully prepared completely linear and specifically branched polymer structures—each tailored for specific processing techniques. At the same time, the melt stability of the material has been significantly improved: the new PBS can withstand temperatures above 200 degrees Celsius, an important breakthrough for industrial applications.

Application verification

In collaboration with industry partners such as Sauer GmbH & Co. KG and Gramß GmbH Kunststoffverarbeitung, the first marketable products have been successfully developed: sports water bottles and matching caps produced using blow molding and injection molding processes. The new PBS material has been tested on standard equipment of industrial plastic processors. The results indicate that the material can be processed stably and efficiently under actual production conditions and exhibits convincing mechanical properties.

Prospects for Development

Dr. Jens Balko, head of the pilot plant for biopolymer processing at Schwarze Heide, is convinced: “As a bio-based and recyclable material, PBS will radically change the landscape of the bioplastics market in the near future and play a key role in the circular plastics economy. With its excellent touch and soft to medium hardness characteristics, PBS can truly replace various products that currently still use polyethylene.”

PBS plastic can be produced using local plant residues. However, the extraction process of succinic acid (a key molecule in PBS synthesis) still needs further development and collaboration with partners.