Plenary - Molecular Recycling of Polyamide 66

Polyamide 66 (nylon 66) provides a unique balance of properties, including high heat tolerance, chemical resistance, electrical insulation, abrasion resistance, and excellent creep resistance. These characteristics make it indispensable in applications such as airbags, parachutes, high-performance tires, athleisure, intimate apparel, high temperature films, automotive components, electrical connectors, to name but a few. However, its inherent crystallinity and durability make recycling challenging, often resulting in downcycling and diminished material properties.

Traditional recycling approaches such as mechanical recycling degrade material performance, restricting recycled nylon 66 to lower-value applications. Advanced techniques like pyrolysis and solutioning have also been explored but with limited success. Pyrolysis breaks nylon 66 into CO, CO₂, and ammonia, requiring complex synthesis to rebuild propylene, acrylonitrile (AN), adiponitrile (ADN), and hexamethylene diamine (HMD). This process is highly inefficient, resulting in poor carbon efficiency and high greenhouse gas emissions. Solutioning, while partially effective, fails to enable fiber-to-fiber conversion and does not restore polymer properties for high-performance applications. Enzymatic recycling faces challenges such as selectivity, scalability, and capital expenditure, while bio-based feedstocks address carbon footprint but not recyclability issues.

Ascend Performance Materials has developed a novel molecular recycling process that addresses these challenges. This innovative approach depolymerizes nylon 66 into an oligomeric state, enabling reformation into high-quality polymer without reverting to monomers or intermediates. This process maintains the material’s performance characteristics and facilitates the production of prime-quality nylon 66 that can be used in high-performance applications, including fiber-to-fiber conversion. Successfully demonstrated at laboratory, pilot, and commercial scales, this approach offers a scalable, sustainable solution that bridges the gap between recycling and performance.

This presentation will delve into the challenges of traditional and emerging nylon 66 recycling methods and highlight how Ascend’s molecular recycling process provides a transformative pathway to sustainable, high-performance material recovery.