Flame retardant FRP systems for light aircraft interior appli-cations

Aircraft interior components are subjected to very high requirements concerning the flame, smoke and toxicity (FST) properties, high mechanical stresses and the price pressure. Because of their high specific strength and stiffness at low weight, fibre-reinforced plastics (FRPs) are very attractive for these applications. Today, FRPs with adequate fire protection are made using phenolic resin, since it has a very good inherent flame resistance. However, its use involves some problems due to e.g. toxic outgassing’s during manufacturing of parts and also in the cured state. Alternatives to phenolic resin exist and are widely used in the industry (e.g. epoxy, polyurethane or polyester resins), but they need to contain high loads of solid flame-retardants to fulfill the FST-requirements. Such highly filled matrices are safe to manufacture compared to phenolic resins and more economical than other resins with inherent flame resistance (such as Benzoxazine resins) and in the cured state harmless, but the production of FRP parts with highly solid-filled matrices is problematic, because of a filter effect of the particles during impregnation.

To produce economically competitive components with the required manufacturing, mechanical and FST properties, alternative materials and manufacturing processes have to be developed and adapted to the specific conditions. Within this research project, three manufacturing technologies (hot pressing of sheet moulding compound (SMC), hot pressing of prepreg and pultrusion) and suitable materials shall be further developed and evaluated. These process technologies seem to be particularly suitable to the aircraft interior applications with regard to cost and energy efficiency.

In a further step, demonstrator parts for different aircraft interior applications are manufactured by use of the developed technologies and materials to demonstrate their technological and economic potential. The demonstrators shall represent the achievable properties and simultaneously serve as a transfer reference for further applications.

Work program:

• Lightweight SMC-sandwich structures with FST-properties
• Modified thermoset and thermoplastic materials in terms of processability, mechanical and FST properties for pregreg impregnation and pultrusion
• Establishing of a low cost prepreg manufacturing process of textile cut outs
• Establishing of low cost pultrusion processes for thermoset and thermoplastic material
• Pultrusion of complex and thin-walled profile geometries
• Manufacturing of demonstrators for different aircraft interior applications and process technologies
• Function integration to reduce lead times of state of the art processes

Partners Hamburg:                                                  Partners Quebec: