Sustainable flame-retardant polyamide compounds? Combining bio-based matrices with glass fiber reinforcement for aviation applications

Abstract The aviation industry is committed to reducing its CO₂ emissions. One approach is the use of materials with a lower carbon footprint. With that in mind, a bio-based polyamide (PA) compound for use in aircraft cabin components is developed. Apart from requirements in high mechanical performance and flame retardancy, the developed material should be appropriate for robot-assisted additive manufacturing (RAM). This manufacturing method allows for a reduction in component weight and, consequently, CO₂ emissions. Since aircraft cabin components are produced in small quantities that require a lot of manual effort during production, RAM is an ideal automated manufacturing method. This study fills a gap in literature, as systematic studies combining bio-based matrices, halogen-free flame retardants (FR), and glass fiber reinforcement are rare. Different FR and their combinations are evaluated in bio-based PA matrices. Additionally, glass fiber reinforcement is used to achieve the desired mechanical properties. The tested PA610 and PA11 have low flammability but poor mechanical properties. The final PA1010-based compound meets all defined requirements and achieves a tensile strength of 102 MPa, an elongation at break of 5%, a notched impact strength of 5.3 kJ/m², and a UL 94 V-0 classification. A life cycle assessment of the final compound, compared to polyetherimide — an established, fossil-based material for these applications — shows clear environmental advantages regarding climate change and fossil resources use . However, it has a higher impact on eutrophication and acidification , which is common for bio-based materials.