Michael Favaloro, global technical marketing manager at Ticona Engineering Polymers (Florence, Ky.), discussed physical attributes and application of linear polyphenylenesulfide (PPS) thermoplastic in composite structures using carbon fiber in aerospace parts and structures. Favaloro noted that there is increasing interest in thermoplastics among aerospace manufacturers, and PPS seems well-positioned to take advantage.
Linear PPS is a semi-crystalline thermoplastic with a melting point of 280°C to 290°C (536°F to 554°F), is inherently flame resistant, resists chemicals and oils (no known solvent below 200°C/392°F), has high hardness and stiffness and can be processed via pultrusion, continuous laminating, compression molding, thermoforming, automated fiber/tape placement, bladder molding and injection molding. As a thermoplastic, the material can be reprocessed, has almost no shelf-life limits and requires no autoclave curing.
Favaloro reviewed carbon fiber/PPS composite use on the Airbus A340/A380 wing leading edge. These structures feature a sheet of PPS film thermoformed with carbon fiber fabric layer to create a curved part that formed the surface of the fixed wing leading edge. Carbon fiber/PPS was also used on press-formed ribs and spars for the Fokker 50 undercarriage door, as well as aileron structures on the Airbus A340. Favaloro also reported that linear PPS is a candidate for several aircraft interior parts, including seat frames, brackets, beams and ducts.