دانلود رایگان مقاله خواص مکانیکی الیاف کامپوزیتی پلی آمید حاوی آمینه عاملدار نانو لوله کربنی

Abstract

Carbon nanotubes (CNTs) have been gained attention and interest to be as ideal reinforcement fillers due to their exceptional theoretical mechanical properties for a long time. To date, the reinforcing effect of the CNTs in most composite systems is still not satisfied. In the present study, by incorporating a novel NH2-MWCNTs/NMP suspension into the polyimide matrix in situ polymerization, a series of PI/NH2-MWCNTs composite fibers have been fabricated using wet-spinning technique. Detailed studies based on different spectroscopic characterizations suggested that there exist multiple interfacial interactions between NH2-MWCNTs and polyimides (PIs) including the hydrogen bonding and π-π interaction. Wide-angle X-ray scattering measurements revealed the evolution of the aggregation structure of these composite fibers during heat-drawing process, and the results illustrated that the incorporated amino functionalized CNTs showed beneficial effects on the packing and orientation of PI molecular chains. Attributed to the above advantages, the resulting composite fiber containing 0.4 wt% NH2-MWCNTs presented a tensile strength of 2.41 GPa (approximately a 47% increase over neat PI fiber), and the modulus of 99 GPa (27% raises compared with neat PI fiber). Meanwhile, dimensional stability of the PI fibers also has been improved by this effective approach.

4. Conclusions

We successfully fabricated PI/NH2-MWCNTs composite fibers with enhanced mechanical properties and dimension stabilities. Utilizing the NH2-MWCNTs/NMP suspension is beneficial for ensuring excellent dispersivity and good compatibility of CNTs in polymer matrix. The reinforcing effects of these 1D cylindrical fillers was implemented by the multiple interfacial interactions between PI and CNTs as well as the facilitating roles of CNTs on the crystallinity and polymer chains orientation of the PI matrix. The PI/ NH2-MWCNTs composite fibers with only 0.4 wt% NH2-MWCNTs content showed a 47% increase in tensile strength and 27% improvement in modulus. These results in this work show a great potential application in fabricating CNT-based PI composite fibers, and may be applied in industrial production.