Biodegradation and up-cycling of polyurethanes: Progress, challenges, and prospects

Area of Science:

• Polymer Science
• Microbiology
• Biotechnology

Background:

• Polyurethanes (PUR) are the 6th most abundant synthetic polymers globally, valued for durability.
• Increasing PUR demand generates substantial waste, necessitating effective disposal and recycling strategies.
• PUR's diverse chemical structures present challenges for biodegradation, despite microbial susceptibility.

Purpose of the Study:

• To review and compare methods for screening polyurethanes (PUR)-degrading microbes and enzymes.
• To summarize catalytic mechanisms involved in PUR biodegradation.
• To present recycling and upcycling strategies for PUR waste, including microbial conversion.

Main Methods:

• Literature review of screening techniques for PUR-degrading microorganisms.
• Comparative analysis of enzymatic catalytic mechanisms for PUR breakdown.
• Compilation of current recycling and upcycling approaches for PUR waste.

Main Results:

• Various methods exist for isolating and characterizing PUR-degrading microbes and enzymes.
• Microbial and enzymatic degradation of PUR is possible, though often slow under natural conditions.
• Effective strategies for PUR waste recycling and upcycling, including bioconversion, are emerging.

Conclusions:

• Identifying efficient PUR-degrading microbes and enzymes is key to a circular PUR economy.
• Understanding degradation mechanisms facilitates the development of novel biorecycling technologies.
• Microbial conversion of PUR monomers offers a pathway to sustainable valorization of plastic waste.