Molecular Orientation and Crystalline Structure of Aligned Electrospun Nylon‐6 Nanofibers: Effect of Gap Size

Abstract

We study the effect of the gap size on the molecular orientation and crystalline structure of uniaxially well‐aligned nylon‐6 nanofibers produced in the gap between negatively charged metal plates. The relative intensities of several absorbance bands are found to be different in the parallel‐ and perpendicularly polarized FTIR spectra. X‐ray analysis indicates that the metastable γ‐form is predominant in as‐spun nylon‐6 nanofibers, and is transformed into the thermodynamically stable α‐form by increasing the gap size. The polymer chains are thought to be oriented perpendicular to the fiber direction, and the molecular orientation to the fiber axis is enhanced on increasing the gap size. magnified image

Handspinning Enabled Highly Concentrated Carbon Nanotubes with Controlled Orientation in Nanofibers

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