The role of grafting force and surface wettability in interfacial enhancement of carbon nanotube/carbon fiber hierarchical composites

• Published in: Carbon (New York) 2014-04, Vol.69, p.239-246
• Main Authors: Wang, Chao, Li, Yibin, Tong, Liyong, Song, Qiang, Li, Kezhi, Li, Jianjun, Peng, Qingyu, He, Xiaodong, Wang, Rongguo, Jiao, Weicheng, Du, Shanyi
• Format: Article
• Language: English
• Subjects: Carbon fibers; Carbon nanotubes; Chemical vapor deposition; Chemistry; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deterioration; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; General and physical chemistry; Grafting; Interfacial properties; Materials science; Mathematical models; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Physics; Solid-fluid interfaces; Solid-liquid interface; Specific materials; Surface physical chemistry; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Wettability; Wetting
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2013.12.020

The grafting force of carbon nanotube (CNT) on carbon fiber (CF) and the wettability of CF surface were experimentally studied, where hierarchical CNT/CF reinforcement was prepared using chemical vapor deposition (CVD). Then, their effects on interfacial improvement were experimentally and theoretically investigated. The results show that the CNT/CF grafting force is so strong, more than 5μN, and CNT/CF attachment can sustain the fracture of the CNTs. This is expected to be contributed to the improvement of interfacial properties. However, the deposited catalyst deteriorates the wettability, which could seriously degrade the interfacial properties. As a result, experimental results from the micro-droplet test show that there is only a 30% increase in the interfacial shear strength of hierarchical CNT/CF reinforced composite comparing with that of as-received CF reinforced composite. An analytical model was developed to predict the effects of CNT/CF grafting force on interfacial improvement, and the predicted results are in agreement with the experimental one.