Continuous carbon fiber (CF)-reinforced poly (ether ether ketone) (PEEK) composites have excellent mechanical properties, but their processing techniques are limited. Therefore, we promoted a braiding method based on the hybrid fiber method by hot-compacting CF/PEEK plain weave fabrics to solve the problem of difficult wetting between CF and PEEK. Four parameters—melting temperature, molding pressure, crystallization temperature and the resin contents—were investigated for optimized fabrication. After studying the melting range, thermal stability and the contact angle of PEEK under different temperatures, the melting temperature was set at 370 °C. An ultra-depth-of-field 3D microscope was adopted to investigate the effects of molding pressure in the melting stage. The tensile strength or modulus along and perpendicular to the carbon fiber direction and crystallinity under different crystallization temperatures were analyzed. As a result, the sample crystalized at 300 °C showed an excellent tensile properties and crystallinity. The increased mass ratio of PEEK ranging from 50.45% to 59.07% allowed for much stronger interfacial strength; however, the higher resin content can lead to the dispersion of CFs, loss of resin and the formation of defects during processing. Finally, the optimal resin mass content was 59.07%, with a tensile strength of 738.36 ± 14.49 MPa and a flexural strength of 659.68 ± 57.53 MPa. This paper studied the optimized processing parameters to obtain better properties from CF/PEEK plain weave fabrics and to further broaden the specific applications of CF/PEEK composites, demonstrating a new direction for its fabrication.

The disposal of industrial wastewater (IWW) discharged from factories is a significant topic in the environment field, and the use of cement-based materials is a useful way to treat materials with unexpected ions. In this work, IWW with abundant SO₄²⁻ collected from a factory was utilized to prepare cement mortar (IWWCM), and three kinds of nanomaterials (NMs), including nano-SiO₂ (NS), nano-CaCO₃ (NC), and nano-metakaolin (NMK), were used to improve the performance of IWWCM. The compressive strengths, hydration degree, hydration products, and micropore structure of the specimens were investigated. The test results showed that IWW reduced the strength of the specimens, and the use of NMs could compensate for this strength reduction. To be specific, the 28-day strength of the freshwater (FW) mixed specimen was 44.6 MPa, and the use of IWW decreased this value to 41.8 MPa. However, the strengths of the specimens with NMs were all higher than 50 MPa, indicating the advantage of NMs for the strengths of the IWWCMs. Moreover, the IWWCM showed a lower hydration degree with a poor pore structure, whereas the use of NMs in IWWCMs refined these properties, explaining the strength increase in the specimens. The results of the SO₄²⁻ content measurements also showed that the use of NMs could improve the SO₄²⁻ binding ratio, which is conducive to relieving the pressure of IWW disposal for industrial factories.