# Polyurethane Recycling: Sustainable Development Perspectives and Innovative Approaches

## TL;DR

This paper reviews polyurethane recycling methods, highlighting chemical and biological approaches that could improve sustainability and reduce environmental impact.

## Contribution

The paper provides a comprehensive review of recent advances and challenges in polyurethane recycling technologies.

## Key findings

- Chemical recycling methods like glycolysis enable recovery of polyols for new polyurethane systems.
- Biological routes offer potential for selective cleavage of polyurethane linkages at low temperatures.
- Mechanical recycling is feasible but reduces material performance, while hybrid strategies show promise for sustainability.

## Abstract

What are the main findings?
Recent advances in catalytic depolymerization, bio-based polyols and NIPU chemistry support transition to circular life cycles.Hybrid strategies show promise for improving material recovery and reducing environmental impact.

Recent advances in catalytic depolymerization, bio-based polyols and NIPU chemistry support transition to circular life cycles.

Hybrid strategies show promise for improving material recovery and reducing environmental impact.

What are the implications of the main findings?
Mechanical recycling remains feasible but reduces mechanical and insulation performance.Chemical recycling enables recovery of polyols suitable for new polyurethane systems.Biological routes show potential for selective cleavage of urethane and ester linkages.

Mechanical recycling remains feasible but reduces mechanical and insulation performance.

Chemical recycling enables recovery of polyols suitable for new polyurethane systems.

Biological routes show potential for selective cleavage of urethane and ester linkages.

Polyurethanes are widely used polymeric materials; their crosslinked structure and compositional diversity significantly hinder effective end-of-life management. The review emphasizes polyurethane recycling technologies, with chemical aspects discussed only insofar as they directly affect recyclability. The influence of polyol and isocyanate structure on phase separation, network architecture and thermal stability is discussed in the context of degradation and depolymerization mechanisms. Mechanical, chemical, thermochemical and emerging biological recycling routes are compared, with emphasis on their respective advantages, limitations and technological maturity. Mechanical recycling remains the most accessible option on an industrial scale but typically leads to reduced mechanical and thermal-insulation performance. Chemical recycling—particularly glycolysis, hydrolysis and aminolysis—enables partial recovery of polyols suitable for reuse in new polyurethane formulations, albeit at the cost of higher energy demand and increased process complexity. The environmental impact of polyurethane recycling is considered in terms of energy consumption, greenhouse-gas emissions, waste-reduction potential and alignment with circular-economy principles. Emerging biological and hybrid recycling strategies are highlighted as promising low-temperature alternatives with potential environmental benefits, despite their current low technological readiness. Key structural and technological barriers to efficient polyurethane recycling are identified, and future research directions toward improved sustainability and resource efficiency are outlined.