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Interfacial Crystallization in Gel-Spun Poly(vinyl alcohol)/Single-Wall Carbon Nanotube Composite Fibers

✍ Scribed by Marilyn L. Minus; Han Gi Chae; Satish Kumar


Publisher
John Wiley and Sons
Year
2009
Tongue
English
Weight
730 KB
Volume
210
Category
Article
ISSN
1022-1352

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✦ Synopsis


Abstract

PVA and PVA/SWNT fibers (PVA = poly(vinyl alcohol), SWNT = single‐walled nanotubes) were processed by gel spinning. At 1 wt.‐% SWNT loading, tensile strength increased from 1.6 GPa for the control PVA to 2.6 GPa for PVA/SWNT composite. Analysis of this data suggests stress of up to ≈116 GPa on the SWNT in the composite fiber. This confirms excellent reinforcement and load transfer of SWNT in the PVA matrix. Tensile modulus of the fiber is also increased from 47 GPa for the control to 70 GPa for the composite. Interfacial studies using high‐resolution transmission electron microscopy reveal extended‐chain crystal growth of PVA at the PVA–SWNT interface. High SWNT alignment in the fiber is revealed, where the polarized Raman G‐band ratio $\left( {{{I_{0^ \circ }^{{\rm VV}} } \mathord{\left/ {\vphantom {{I_{0^ \circ }^{{\rm VV}} } {I_{90^ \circ }^{{\rm VV}} }}} \right. \kern-\nulldelimiterspace} {I_{90^ \circ }^{{\rm VV}} }}} \right)$ is as high as 106. Composite fiber shrinkage in water is reduced by ∼70% when compared to the control PVA fibers.

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📜 SIMILAR VOLUMES


Observations on Solution Crystallization
✍ Marilyn L. Minus; Han Gi Chae; Satish Kumar 📂 Article 📅 2010 🏛 John Wiley and Sons 🌐 English ⚖ 580 KB

## Abstract PVA/SWNT dispersions yield __aloe plant__‐like crystals, where the __leaves__ are single crystals templated by PVA coated SWNT. Longer growth times (≈18 months) lead to __hexagonal rod__‐like crystals. HR‐TEM images show evidence that PVA molecules are aligned parallel to the SWNT axis.