Debondable adhesive for improved PET bottle recyclability through easy label removal

Overview

Conagen has invented a debondable adhesive that can be tuned to melt at any desired temperature. The proposed solution applies this adhesive technology to PET bottle labels, enabling easy label removal after product use and improving the purity of PET recycling inputs. By facilitating simple separation of label material from bottle material, this approach addresses a key challenge in PET recycling where residual labels and adhesives contaminate the recycled stream.

The adhesive leverages dynamic chemical bonds derived from Conagen's proprietary fermented ingredients, originally developed for food applications. The technology has demonstrated strong bonding performance comparable to or better than conventional adhesives across multiple substrates, with the added benefit of clean debondability at elevated temperatures.

Technical specifications

Core technology features:

• Tunable melting temperature allowing the adhesive to be engineered for specific application requirements
• Dynamic chemical bonds enabling strong initial adhesion with clean, easy debonding on demand
• Bio-based fermented ingredients providing the foundation for adhesive strength and reversibility
• Compatibility with diverse substrates including soft materials (textiles, plastics) and hard materials (metals, metal oxides)
• Self-bonding and hybrid materials bonding capabilities

Key applications demonstrated or in development:

• Packaging labels for PET bottles and other food packaging
• Clothing and soft goods manufacturing
• Electronics OEM assembly
• Automotive interior manufacturing
• Tier 1 adhesive supplier partnerships

The adhesive is currently undergoing intensive testing by clothing brands, softgood manufacturers, electronics OEMs, automotive interior OEMs, and adhesive Tier 1 suppliers.

Technology readiness level

The debondable adhesive has been validated across multiple substrate types and applications in electronics and textiles industries. Conagen holds several patent applications scheduled to publish in September 2023.

For the specific application of PET bottle label removal, the technology requires approximately one year of additional development, including materials synthesis, formulation optimization, adhesive testing, mechanical properties characterization, and strain improvement for the fermentation-derived ingredients. This work would require two full-time equivalents, one focused on material science and one on strain improvement.

The proposal seeks validation testing and formulation development to meet the specific metrics required for a debondable adhesive suitable for packaging labels, representing a focused extension of an already-proven technology platform into a new high-impact application area.