Recycling bio-based polyesters for sustainable packaging

Overview

This offering addresses the growing need for circular-economy solutions in the plastics industry by combining mechanical and chemical recycling methods to reclaim monomers and oligomers from bio-based aliphatic polyesters. The approach is designed for sustainable packaging applications and draws on extensive prior experience in recycling polyurethanes, polyamides, PET, and multilayer packaging. By recovering high-value building blocks from polymer waste, the technology supports closed-loop manufacturing, reduces reliance on fossil-derived feedstocks, and enables the production of new polymeric materials with comparable or improved performance.

Technical specifications

Key features:

• Glycolysis pathway: Uses glycols as cleavage agents for polyester-based polymers, with optimization of glycol type, temperature, and reaction duration to maximize monomer and oligomer yield.
• Selective dissolution pathway: Applies tailored solvents selected using Hildebrand solubility parameter theory to separate and recover polymers from multilayer packaging waste streams.
• Mechanical pre-processing: Mills polymer residues into flakes or powder, with granulometry optimized to maximize downstream recycling efficiency.
• Separation and recovery: Employs precipitation and filtration techniques to isolate purified monomers, oligomers, or polymers suitable for reintroduction into production.
• Feedstock flexibility: Applicable to bio-based aliphatic polyesters and adaptable to mixed or multilayer packaging formats.
• End-use integration: Recovered materials can be used alone or blended with virgin polymers to manufacture new plastic products.

Technology readiness level

The underlying recycling concepts have been validated across multiple polymer systems, including polyurethane acidolysis, mechanical PU recycling for composites and 3D printing, polyamide recycling with organic and inorganic acids, PET glycolysis, and ongoing work on multilayer packaging dissolution. These prior validations demonstrate the feasibility of each individual step. The next phase will focus on extending the validated glycolysis and selective dissolution approaches specifically to bio-based aliphatic polyesters, optimizing process parameters, and confirming that the resulting recycled materials meet specifications for new packaging and polymer applications.