Lu Chunrui, Wang Jian, Lu Xue, Zheng Ting, Liu Yingyi, Wang Xiaodong, Zhang Dongxing, Seveno David
School of Materials Science and Engineering , Harbin Institute of Technology , Harbin 150001 , China.
Department of Materials Engineering , KU Leuven , Leuven 3001 , Belgium.
ACS Appl Mater Interfaces. 2019 Aug 28;11(34):31520-31531. doi: 10.1021/acsami.9b09735. Epub 2019 Aug 16.
Studies on carbon fiber (CF)/poly(ether ether ketone) (PEEK) fiber hybrid textiles were initiated several decades ago because their flexibility and conformability make them a promising alternative to traditional prepregs. The adhesion between the CFs and PEEK is mostly controlled by their inherent surface properties and mutual wettability. However, details of these properties remain largely unknown, especially those of PEEK. Therefore, to determine the surface and interfacial properties of these fibers, we performed a comprehensive study and characterized their surface topography (atomic force microscopy, scanning electron microscopy), surface chemistry [X-ray photoelectron spectrometry (XPS), acid-base titration], surface energies (wetting tests, acid-base approach), and interfacial mechanical properties [droplet test, interfacial shear strength (IFSS)]. These experiments were complemented by a theoretical approach to the prediction of the surface energy components (parachor) and contact angles of PEEK. We found good agreement between the results obtained by XPS and wetting tests (base-to-acid surface energy component ratio), as well as between the predicted and measured surface energy and contact angles. The results highlight the consistency and reliability of the proposed methodology. We found that both CFs and PEEK fibers appear to be smooth at the nanoscale and have large dispersive and basic surface energy components. The IFSS of CF/PEEK is significantly higher (44.87 ± 5.76 MPa) compared to that of other thermoplastic systems. The findings not only demonstrate the potential of CF/PEEK hybrid textiles but also emphasize the need to further increase the compatibility between CFs and PEEK fibers by increasing the acidic component of CF surfaces. Surface treatments and the design of a suitable sizing are potential methods to achieve this objective in future studies.
几十年前就开始了对碳纤维（CF）/聚醚醚酮（PEEK）纤维混杂织物的研究，因为它们的柔韧性和贴合性使其成为传统预浸料的一个有前途的替代品。CF与PEEK之间的粘附力主要由它们固有的表面性质和相互润湿性控制。然而，这些性质的细节在很大程度上仍然未知，尤其是PEEK的那些性质。因此，为了确定这些纤维的表面和界面性质，我们进行了一项全面的研究，并对它们的表面形貌（原子力显微镜、扫描电子显微镜）、表面化学[X射线光电子能谱（XPS）、酸碱滴定]、表面能（润湿性测试、酸碱方法）和界面力学性能[液滴测试、界面剪切强度（IFSS）]进行了表征。这些实验辅以一种预测PEEK表面能成分（等张比容）和接触角的理论方法。我们发现XPS和润湿性测试（碱对酸表面能成分比）得到的结果之间，以及预测和测量的表面能与接触角之间有很好的一致性。结果突出了所提出方法的一致性和可靠性。我们发现CF和PEEK纤维在纳米尺度上似乎都是光滑的，并且具有大的色散和碱性表面能成分。与其他热塑性系统相比，CF/PEEK的IFSS显著更高（44.87±5.76MPa）。这些发现不仅证明了CF/PEEK混杂织物的潜力，而且强调了通过增加CF表面的酸性成分来进一步提高CF与PEEK纤维之间相容性的必要性。表面处理和合适上浆剂的设计是未来研究中实现这一目标的潜在方法。
