Tie Layers for Recyclable Barrier Films


Project ID: D2022-11


Multilayer packaging consists of thin layers of materials adhered on top of one another. The composition of layers is chosen based on performance needs, such as protection from moisture, oxygen, light, odor, flavor, or abrasion. Although these varying material properties contribute to performance advantages, they also interfere with the separation techniques that are leveraged in the recycling process. Current methods of recycling multilayer packaging require deviations from a typical recycling plant, such as requiring antisolvent recovery steps or high concentrations of chemicals for delamination.

Invention Description

Researchers at the University of Toledo have designed coacervates as smart tie layers that dissolve on demand. The coating and tie layer materials form spontaneously on mixing unsaturated fatty acids with polyamines. A uniform film can be made with >100 kPa lap-shear adhesion strengths. Researchers have validated this with HDPE, PP, EVOH, and PA. Once ready for disposal, the plastic films can be recycled using traditional recycling techniques for delamination and density-based separations. 


  • Smart tie layers for multilayer films
  • Oxygen barrier for packaging
  • Sustained release of chemicals, flavors, drugs, etc. 
  • Solute uptake for chemical separations
  • Sealant or adhesive


  • Spontaneous charge-driven self-assembly
  • Integrates into current recycling systems
  • Biobased
  • Organic solvent-free

IP Status:                    Patent Pending

Patent Information:
For Information, Contact:
Yuriy Yatskiv
Licensing Associate
The University of Toledo
Yakov Lapitsky
Maria Coleman
Joseph Lawrence
Jose Carlos Benalcazar Bassante