Abstract
Liquid crystal polymer (LCP) nanofibers were prepared by electrospinning from isotropic and biphasic poly(γ-benzyl-L-glutamate) (PBLG)/dichloromethane–pyridine solutions. The prepared fibers were characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, polarized optical microscopy, wide-angle X-ray diffraction and polarized micro-Raman spectroscopy. The as-spun PBLG fiber from the isotropic solutions had an undulating orientation of closed-packed α-helices similar to a serpentine trajectory in their internal structures. The as-spun PBLG fibers from the biphasic solutions that contained the LC phase had uniaxially oriented hexagonal lattices of α-helices along the fiber axis. These results indicated that the orientation of the ordered structure of the electrospun lyotropic LCP fibers can be controlled by the initial microstructure of the spinning solution.
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Acknowledgements
We thank Professor Hideo Takezoe, Associate Professor Masatoshi Tokita and Dr Tsuyoshi Michinobu, Tokyo Institute of Technology, for assistance with the polarized micro-Raman spectroscopy, WAXD and FT-IR/ATR measurements, respectively. This study was partly supported by the New Energy and Industrial Technology Department Organization (NEDO).
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Tsuboi, K., Marcelletti, E., Matsumoto, H. et al. Preparation of poly(γ-benzyl-L-glutamate) nanofibers by electrospinning from isotropic and biphasic liquid crystal solutions. Polym J 44, 360–365 (2012). https://doi.org/10.1038/pj.2011.137
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DOI: https://doi.org/10.1038/pj.2011.137
