Polyamide (PA) is increasingly valued in the packaging industry for its durability and high-performance properties, though questions remain about its acceptance in recycling streams.
Dr. Roland Bothor from Institut cyclos-HTP GmbH (CHI), a neutral and independent leader in testing and certification of recyclability, provides insight into polyamide’s role in sustainable packaging and the necessary steps for successful recycling.
Q: What advantages does polyamide offer in packaging?
CHI: Polyamide, particularly PA6, offers notable mechanical strength and flexibility, making it ideal for high-stress applications like injection moulding and extrusion. Polyamide provides improved mechanical toughness in end-use applications, allowing it to perform in more demanding contexts. When properly designed, polyamide is a valuable material with advantageous properties, supporting its sustainable role in packaging.
Q: How does CHI evaluate the recycling compatibility of polyamide?
CHI: We conduct compatibility tests to simulate the performance of polyamide in real recycling conditions and as a minor component in PCR using a commercially available PCR from the relevant recycling stream as reference. By introducing polyamide-containing samples into waste streams at varying concentrations, we can observe their behaviour in recycling processes and evaluate the quality of the resulting PCR recyclates. Any reduction of the properties of relevant recyclate applications, such as blown films, lead to a negative result in our standard. Equal or positive properties lead to our classification as “recycling compatible”, and this is the case of polyamide in both co-extruded and compatibilizer-containing laminated PE films. In fact, thoughtful design elements can significantly improve the recyclability of polyamide, making it a viable option in targeted packaging formats.
Q: What guidance can you give on designing polyamide-containing packaging for recycling?
CHI: We recommend a balanced approach that considers material compatibility, especially between polyamide and polyethylene in coextruded structures. Ensuring appropriate polyamide-to-tie layer ratios as needed and adding compatibilisers where recommended can notably improve recyclability of polyethylene films. In laminated structures without tie layers the use of a compatibiliser as additive e.g. in the polyethylene layer is necessary to ensure the recycling compatibility of the structure. When a polyamide layer is thoughtfully integrated, it not only preserves the quality of the packaged goods but also allows for efficient recycling, supporting a circular approach to packaging design.
Q: What are the next steps to improve the recyclability and acceptance of polyamide?
CHI: Transparency is crucial. We advocate for publishing testing results and engaging the public with science-backed information to clarify any misconceptions about polyamide. As the APA highlights, collaborating with recyclers and converters ensures that recycling compatibility is integrated into the design process, ultimately positioning polyamide as a fully accepted material in sustainable packaging.
Polyamide in packaging: Performance and recycling guidance
Thoughtful design and evidence-based advocacy validate polyamide-containing packaging as a recyclable, sustainable choice that meets both industry and regulatory standards. By supporting these initiatives, organisations like the Advanced Packaging Association (APA) and independent research institutes like CHI are encouraging the industry to view polyamide not as a challenge, but as a valuable component in achieving sustainable packaging goals.