Spore-bearing biocomposite TPU is a promising alternative elastomer for manufacturers

A spore-bearing biocomposite thermoplastic polyurethane (TPU) is a promising alternative elastomer that could be used to manufacture popular items such as footwear, phone cases and automotive parts, according to a new study from a team that includes researchers from the UGA New Materials Institute.

Researchers from the UGA NMI have been helping to validate this new TPU, which was developed by researchers from the University of California San Diego by modifying a polymer from the BASF Corporation. The composite incorporates live bacterial spores from a strain of Bacillus subtilis that are combined with TPU pellets in a plastic extruder.

TPUs rank as the sixth-most produced polymer worldwide, with increasing demand for their use, but only 0.3% of these plastics are recycled in the United States; most are landfilled, incinerated, or leach into the environment as uncontrolled waste. TPUs are used widely in society, due to their exceptional flexibility, rigidity, and resistance to abrasion.

In their latest work, the study team explored modifying spore production to control the color output without compromising spore productivity, viability, morphology or heat-shock tolerance. They also demonstrated manufacturing capabilities, such as scaled-up fabrication using a continuous extruder followed by injection molding. Their work confirmed that spore-bearing TPUs show excellent feasibility in terms of tensile properties, scalability, recyclability and longevity.

The UGA NMI team developed some of the extrusion methods and injection molding conditions used in this study. Biodegradation studies were not part of this work but were previously conducted in the UGA NMI’s Bioseniatic℠ Laboratory.

“Scalable fabrication of a tough and recyclable spore-bearing biocomposite thermoplastic polyurethane,” was recently published in the Chemical Engineering Journal. Co-authors include Han Sol Kim, Myung Hyun Noh, Adam Feist and Jonathan K. Pokorski, of the University of California San Diego; Md Arifur Rahman, of BASF Corporation; Evan M. White, Grant Crane, Kush Patel, and Jason Locklin, of the UGA New Materials Institute.

Their work was supported by BOTTLE™ consortium (# DE-EE0009296) grant funded by the U.S. Department of Energy’s (DOE’s) Office of Energy Efficiency and Renewable Energy (EERE) and Advanced Manufacturing Office (AMO).