Preparation of Poly(N-vinylformamide) Nanofibers and Study of Molecular Orientation in the Fibers

• Main Authors: Tsun-TeWang, 王存德
• Other Authors: Sheng-Shu Hou
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/08754047892934461202

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 98 === In the present study, we have synthesized poly(N-vinylformamide) via free radical polymerization in aqueous phase. The polymer is a non-toxic, biocompatible, and hydrophilic for applying in biomedical field. In electrospinning, the PNVF/H2O system leads to form junctions due to solvent easily. For preventing the results, the PNVF/H2O/EtOH system was prepared for improving the solution parameters. The factors that affect the fiber morphology and average diameter such as the solution parameters and the processing conditions have been investigated. In the effect of voltage, we found the fiber average diameter is 97 ± 21 nm at 15 kV. There’s a limit for diameter as increased flowrate. The average diameter of fibers reduced as the distance increasing. Besides, the aligned nanofibers were prepared by electric field inducing, and we study the isotropic nanofibers and the aligned nanofibers through polarized FTIR. We also deconvolve the peaks of C=O and N-H by using PeakFit. We study the relationship between the molecular orientation and the angles such as 0o and 90o which are between the polarization vector of infrared radiation and the draw direction of fibers. The chains in fibers orientate along the draw direction of fibers have been investigated, and this results to the peak area ratio of C-N trans- to C-N cis- at 90o is 5.55. Moreover, the peak intensities of almost functional groups at 0o are larger than that at 90o. Finally, we discover the peak area ratio of hydrogen-bonded C=O to free C=O at 0o is 7.76, and the ratios of hydrogen-bonded N-H to free N-H at 0o and 90o are 5.16 and 5.28.