Microbial and Enzymatic Biodegradation of Polyurethane: From Depolymerization to Monomer Valorization

Area of Science:

• Polymer Science
• Environmental Science
• Biotechnology

Background:

• Polyurethane (PU) is a major global plastic, generating significant waste and microplastic pollution.
• Current PU waste management faces challenges like resource depletion and environmental contamination.
• Existing recycling methods often lack efficiency and sustainability.

Purpose of the Study:

• To systematically review advances in microbial and enzymatic biodegradation of polyurethane (PU).
• To discuss metabolic pathways for depolymerized PU monomers.
• To explore resource utilization strategies for PU waste, including closed-loop recycling and upcycling.

Main Methods:

• Literature review of PU chemical structures, biodegradation processes, and microbial/enzymatic catalysts.
• Analysis of biological metabolic pathways for PU monomers.
• Examination of current strategies for PU waste resource utilization.

Main Results:

• Microbial and enzymatic catalysts enable efficient PU depolymerization under mild conditions, avoiding organic solvents.
• Significant progress has been made in identifying PU-degrading microbes and enzymes.
• Challenges remain in biocatalyst availability, depolymerization efficiency, and recovery/reuse.

Conclusions:

• Enzymatic and microbial PU biodegradation presents a promising green and low-carbon end-of-life treatment.
• Further research is needed to overcome current limitations for industrial application.
• Developing efficient biodegradation and recovery methods supports a circular plastic economy, sustainability, and carbon neutrality goals.