Bacteria added to plastic to enhance biodegradability

Led by a team at the University of California San Diego, the research has developed a biodegradable form of thermoplastic polyurethane (TPU), a melt-processable thermoplastic elastomer found in footwear, floor mats, cushions and memory foam.

The TPU is filled with bacterial spores that, when exposed to nutrients present in compost, germinate and break down the material at the end of its life cycle. The work is detailed in Nature Communications.

The biodegradable TPU was made with bacterial spores from a strain of Bacillus subtilis that breaks down plastic polymer materials.

“It’s an inherent property of these bacteria,” said study co-senior author Jon Pokorski, a nanoengineering professor at the UC San Diego Jacobs School of Engineering and co-lead of the university’s Materials Research Science and Engineering Center (MRSEC). “We took a few strains and evaluated their ability to use TPUs as a sole carbon source, then picked the one that grew the best.”