Study of the influence of PPS, PAEK, and PEEK thermoplastic matrices on the static mechanical behavior of carbon fiber-reinforced composites

The growing use of poly(phenylene sulfide) (PPS), poly(aryl ether ketone) (PAEK), and poly(ether ether ketone) (PEEK) polymers reinforced with carbon fiber (CF) aims to meet the increasing demand for structural thermoplastic composites in applications that require excellent mechanical properties and thermal stability at higher temperatures (for example, above 120 degrees C). The present work studied the influence of semicrystalline thermoplastic matrices of PPS, PAEK, and PEEK on the static mechanical behavior of CF-reinforced composites through tensile tests and fractographic analysis of the respective fracture surfaces. The results of mechanical tests showed that the matrix influenced the static properties of the composites, mainly in stiffness, highlighting the CF/PEEK composite with the highest stiffness (42.3 +/- 0.5 GPa) and the CF/PPS with the lowest standard deviation in tensile strength (599 +/- 12 MPa). The fractographic analyses showed the good quality of the laminates, which presented an excellent matrix-reinforcement interface, without fiber detachment or pulling out after mechanical tests, guaranteeing the transfer of efforts from the matrix to the reinforcement.