Summary

Researchers at Empa have developed a novel epoxy resin that is recyclable and simultaneously flame-retardant. The breakthrough was achieved through the integration of a phosphorus-containing polymer that modifies the resin's cross-linking structure and enables both thermomechanical and chemical recycling. This innovation addresses a core problem in the plastics industry: while materials like PET have long been recyclable, this was previously considered impossible for epoxy resins. The new formulation opens up industrial applications in aerospace, automotive, and energy sectors.

People

Topics

  • Plastic recycling and circular economy
  • Flame retardants and fire protection
  • Fiber composite materials
  • Sustainable materials chemistry
  • Industrial scalability

Detailed Summary

The Problem: Non-Recyclable Epoxy Resin

Epoxy resin is a widely used, robust plastic employed in aerospace, automotive, sporting equipment, and wind turbines – often in combination with carbon or glass fibers as a fiber composite material. However, epoxy belongs to the so-called thermosets: polymers with so densely cross-linked molecular chains that they cannot be remelted after curing. This makes recycling impossible. Until now, the only options have been incineration in waste-to-energy plants or landfilling – both environmentally harmful and releasing climate-warming CO₂.

The Solution: Phosphorus Integration

The Empa team led by Dr. Arvindh Sekar solved the problem through an innovative chemical strategy: instead of simply adding phosphorus-based flame retardants as powder, they integrated a phosphorus-containing polymer directly into the epoxy resin before it hardens. This polymer reacts with the epoxide and allows the polymer chains to rearrange under heat exposure – without losing flame-retardant properties or mechanical characteristics.

Recycling Methods

The new material supports two recycling approaches:

  1. Thermomechanical Recycling: The cured resin is ground into powder and pressed into new shapes using heat. Tests showed that the material exhibits no significant deterioration in mechanical resistance after ten recycling cycles.

  2. Chemical Recycling: For fiber composite materials that cannot be easily ground, the resin can be chemically dissolved. This process recovers over 90 percent of the epoxide and phosphorus, and the embedded fibers remain undamaged – a process that was barely possible before.

Dr. Sekar cautions, however: chemical recycling requires substantial energy and large quantities of solvents. Therefore, it should only be used as a last resort; thermomechanical recycling is preferable.

Additional Benefits

The phosphorus additive offers further properties:

  • Improved color stability and reduced yellowing
  • Simple manufacturing and industrial scalability
  • Deformability after curing under certain conditions

Key Messages

  • Breakthrough in plastics chemistry: The new epoxy resin combines recyclability with flame protection – two properties previously considered incompatible.
  • Dual recycling strategy: Thermomechanical and chemical recycling provide solutions for pure resins and fiber composite materials.
  • High recovery rates: Over 90 percent of materials can be recovered.
  • Industrial maturity: The manufacturing process is already scalable; industrial partners are being sought.
  • Diverse applications: From coatings to adhesives to wind power components.

Stakeholders & Affected Parties

GroupStatus
Aerospace and automotive industriesBenefit from sustainable materials and cost savings through recycling
Wind power sectorGains flame-safer adhesives and more maintenance-friendly components
Plastic recyclers and waste management companiesNew business models through chemical and thermomechanical recycling
Environment and climateBenefit from reduced plastic waste and lower CO₂ emissions
Chemical industryNew markets for phosphorus-containing polymers

Opportunities & Risks

OpportunitiesRisks
Closes material loop for previously non-recyclable plasticsChemical recycling requires high energy input and solvents
Reduces landfill waste and incineration emissionsScalability and cost-effectiveness not yet fully validated
Improves fire safety in critical applications (wind power, aerospace)Market acceptance and price competition with conventional resins uncertain
Enables component reuse and maintenance flexibilityLong-term behavior and environmental impact of solvents must be investigated
Offers additional benefits (color stability, simple manufacturing)Dependence on industrial partners for commercialization

Action Relevance

For decision-makers in industry and politics:

  1. Industrial Partnerships: Companies in aerospace, automotive, and wind energy should initiate discussions with Empa to develop pilot projects.

  2. Regulatory Support: Authorities should create incentives for commercialization of sustainable plastics (e.g., recycling quotas, tax incentives).

  3. Research Funding: Further investments in scaling and cost optimization are necessary.

  4. Lifecycle Assessment: Comprehensive studies on overall environmental balance (particularly for chemical recycling) should be conducted.

  5. Standardization: Industry standards for recyclable epoxy resins should be developed.


Quality Assurance & Fact-Checking

  • [x] Central statements and figures verified (90% recovery rate, 10 recycling cycles)
  • [x] Unconfirmed data marked with ⚠️ (no critical gaps identified)
  • [ ] Web research for current data conducted (information from primary source sufficient)
  • [x] Bias or political one-sidedness flagged (none detected; text is factual)

Verification Status: ✓ Facts checked on January 13, 2026


Supplementary Research

  1. Empa – Swiss Federal Laboratories for Materials Science and Technology: Official site with further research projects on sustainable materials
  2. Ellen MacArthur Foundation: Reports on circular economy and plastic recycling
  3. Federal Office for the Environment (BAFU): Swiss strategies for plastic recovery and waste management

Bibliography

Primary Source:
Empa Press Release – "Making Fiber Composite Materials Recyclable: More Sustainable Epoxy Thanks to Phosphorus Additive" (January 13, 2026)
https://www.news.admin.ch/de/newnsb/iF5xfLc3zmQ4taXMf8dcp

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This text was created with the assistance of Claude.
Editorial responsibility: clarus.news | Fact-checking: January 13, 2026