| Abstract
| - The electrospinning process was used successfully to embed single-walled carbon nanotubes (SWCNTs)in a poly(ethylene oxide) (PEO) matrix, forming composite nanofibers. Initial dispersion of SWCNTs inwater was achieved by the use of an amphiphilic alternating copolymer of styrene and sodium maleate.The resulting dispersions were stable, having a dark, smooth, ink-like appearance. For electrospinning,the dispersions were mixed with PEO solution in an ethanol/water mixture. The distribution andconformation of the nanotubes in the nanofibers were studied by transmission electron microscopy (TEM).Oxygen plasma etching was used to expose the nanotubes within the nanofibers to facilitate directobservation. Nanotube alignment within the nanofibers was shown to depend strongly on the quality ofthe initial dispersions. Well-dispersed and separated nanotubes were embedded in a straight and alignedform, while entangled nonseparated nanotubes were incorporated as dense aggregates. X-ray diffractiondemonstrated a high degree of orientation of the PEO crystals in the electrospun nanofibers with embeddedSWCNTs. This result is in pronounced distinction to the detrimental effect of incorporation of multiwalledcarbon nanotubes on polymer orientation in electrospun nanofibers, as reported previously.
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