Kinetic analysis of thermo-oxidative degradation of PEEK/thermotropic liquid crystalline polymer blends

Laser Ablation Mechanism and Performance of Carbon Fiber-Reinforced Poly Aryl Ether Ketone (PAEK) Composites

The ablation mechanism and performance of carbon fiber (CF)-reinforced poly aryl ether ketone (PAEK) thermoplastic composites were studied in this paper. The results show that the ablation damaged area is controlled by the irradiation energy, while the mass loss rate is controlled by the irradiation power density. In the ablation center, the PAEK resin and CFs underwent decomposition and sublimation in an anaerobic environment. In the transition zone, the resin experienced decomposition and remelting in an aerobic environment, and massive char leaves were present in the cross section. In the heat-affected zone, only remelting of the resin was observed. The fusion and decomposition of the resin caused delamination and pores in the composites. Moreover, oxygen appeared crucial to the ablation morphology of CFs. In an aerobic environment, a regular cross section formed, while in an anaerobic environment, a cortex–core structure formed. The cortex–core structure of CF inside the ablation pit was caused by the inhomogeneity of fibers along the radial direction and the residual carbon layer generated by resin decomposition in an anoxic environment. The description of the ablation mechanism presented in this study broadens our understanding of damage evolution in thermoplastic composites subjected to high-energy CW laser irradiation.

Novel melt-processable poly(ether ether ketone)(PEEK)/inorganic fullerene-like WS(2) nanoparticles for critical applications

The combination of high-performance thermoplastic poly(ether ether ketone) (PEEK) with inorganic fullerene-like tungsten disulfide (IF-WS(2)) nanoparticles offers an attractive way to combine the merits of organic and inorganic materials into novel polymer nanocomposite materials. Here, we report the processing of novel PEEK/IF-WS(2) nanocomposites, which overcome the nanoparticle agglomerate formation and provide PEEK-particle interactions. The IF-WS(2) nanoparticles do not require exfoliation or modification, making it possible to obtain stronger, lighter materials without the complexity and processing cost associated with these treatments. The nanocomposites were fabricated by melt blending, after a predispersion step based on ball milling and mechanical treatments in organic solvent, which leads to the dispersion of individually IF-WS(2) nanoparticles in the PEEK matrix as confirmed by scanning electron microscopy. In order to determine the performance of the PEEK/IF-WS(2) nanocomposites for potential critical applications, particularly for the aircraft industry, we have extensively investigated these materials with a wide range of structural, thermal, and mechanical techniques using time-resolved synchrotron X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, dynamic-mechanical analysis, and tensile and impact tests as well as thermal measurements. Modulus, tensile strengh, thermal stability, and thermal conductivity of PEEK exhibited remarkable improvement with the addition of IF-WS(2).