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Abstract Carbon nanotube (CNT)‐reinforced polymer fibers have broad applications in electrical, thermal, optical, and smart applications. The key for mechanically robust fibers is the precise microstructural control of these CNTs, including their location, dispersion, and orientation. A new methodology is presented here that combines dry‐jet‐wet spinning and forced assembly for scalable fabrication of fiber composites, consisting of alternating layers of polyacrylonitrile (PAN) and CNT/PAN. The thickness of each layer is controlled during the multiplication process, with resolutions down to the nanometer scale. The introduction of alternating layers facilitates the quality of CNT dispersion due to nanoscale confinement, and at the same time, enhances their orientation due to shear stress generated at each layer interface. In a demonstration example, with 0.5 wt% CNTs loading and the inclusion of 170 nm thick layers, a composite fiber shows a significant mechanical enhancement, namely, a 46.4% increase in modulus and a 39.5% increase in strength compared to a pure PAN fiber. Beyond mechanical reinforcement, the presented fabrication method is expected to have enormous potential for scalable fabrication of polymer nanocomposites with complex structural features for versatile applications.
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Laser Processing Technology for PAN Fiber Carbonization
Carbon fibers (CFs) are an important engineering material due to their superior mechanical, electrical, and thermal properties. Majority of them are produced from the thermal conversion of polyacrylonitrile (PAN)-based fibers. In order to promote the CF manufacturing speed and offer the possibility to control the microstructure of the fibers, an alternative technology for carbonization of stabilized PAN fiber are explored by laser processing technology. In this work, we investigated the relationship between the laser process and the properties of fibers. Laser irradiation introduces the structural changes in the stabilized PAN fibers. The appearance of D band and G band in Raman spectrum verifies the existence of graphite structures in the laser scanned fibers. The characteristic peaks in FTIR disappear when the high laser energy condition is engaged, which indicates diminishing of non-carbon bonds. Laser treatment also introduces an obvious shrinkage in fiber diameter. The condition of laser irradiation could influence the electrical and mechanical properties of fibers. A new approach to convert stabilized PAN fiber into carbon fiber was demonstrated.
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- Award ID(s):
- 1635550
- PAR ID:
- 10087769
- Date Published:
- Journal Name:
- The Composites and Advanced Materials Expo. CAMX Conference Proceedings
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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