Yin Changping, Sheng Liping, Yang Yudong, Liang Gengyuan, Xing Suli, Zeng Jingcheng, Xiao Jiayu
College of Aerospace Science and Engineering, National University of Defense Technology Changsha 410073 P. R. China.
National Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University Changsha 410081 P. R. China
RSC Adv. 2018 Nov 14;8(67):38210-38218. doi: 10.1039/c8ra07680d.
There has been little research focus on the interface problems of phthalonitrile (PN) resin and carbon fiber. However, interface performance is related to the overall mechanical properties of composites and is very important. This study focused on the interfacial performance and adhesion mechanism of a carbon fiber C/PN composite. Micro-composites of C/PN and C/epoxy resins were prepared, and their interfacial shear strengths (IFSS) were tested by micro-droplet testing. The result showed that the IFSS of C/PN was higher than that of C/epoxy resin, indicating that the interfacial adhesion of the PN matrix composite must be more effective. To explain the obtained results, a number of tests, including SEM, SEM-EDS, FTIR, and TGA, were carried out. From the SEM analyses, cured PN polymer films were found on the surface of de-bonded carbon fibers. With the aid of SEM-EDS, the elements on the de-bonded carbon fiber surface of the C/PN composite were detected . An interesting synchronous relationship was observed in the IFSS and SEM-EDS results. Through the FTIR spectra, the chemical structures of the PN polymers were identified. From the detailed analyses and discussion in this work, the effective interfacial bond function in the C/PN composite appears to be a complex result for all relative functions. The functional advantage of the PN composite may be the interface conjugation between the PN polymers and the graphene layer on the surface of the carbon fiber.
关于邻苯二甲腈（PN）树脂与碳纤维的界面问题，此前鲜有研究关注。然而，界面性能与复合材料的整体力学性能相关，且非常重要。本研究聚焦于碳纤维C/PN复合材料的界面性能及粘结机理。制备了C/PN和C/环氧树脂的微复合材料，并通过微滴试验测试了它们的界面剪切强度（IFSS）。结果表明，C/PN的IFSS高于C/环氧树脂，这表明PN基复合材料的界面粘结必定更有效。为解释所得结果，进行了包括扫描电子显微镜（SEM）、扫描电子显微镜-能谱分析（SEM-EDS）、傅里叶变换红外光谱（FTIR）和热重分析（TGA）在内的多项测试。从SEM分析中发现，在脱粘碳纤维表面存在固化的PN聚合物薄膜。借助SEM-EDS，检测了C/PN复合材料脱粘碳纤维表面的元素。在IFSS和SEM-EDS结果中观察到一种有趣的同步关系。通过FTIR光谱，确定了PN聚合物的化学结构。通过本工作中的详细分析和讨论，C/PN复合材料中有效的界面键合作用似乎是所有相关作用的复杂结果。PN复合材料的功能优势可能在于PN聚合物与碳纤维表面石墨烯层之间的界面共轭。
