Preparation And Characterization Of PVP-I₂ Nanofibers By Electrospinning Technique

Recently, the electrospinning technique has attracted increasingly worldwide attention. The as-electrospun nanofibers have many advantages, such as large surface area and high porosity. Many polymers such as polyethylene oxide (PEO), polyvinyl alcohol (PVA), nylon, poly vinyl pyrrolidone (PVP) have been electrospun into nanofibers. Therein, PVP is an excellent, versatile water-soluble, high value-added fine chemical product, which is deemed as an international advocate of the important chemical and pharmaceutical intermediates. Besides, iodine, as a bactericidal material, has low toxicity and high efficiency, long-aging effect, and therefore its application of sterilization becomes more important. However, low water solubility still restricts its application. In order to expand the application of iodine, there is a need for loading of iodine on the PVP polymer to form amorphous compounds, PVP- I2. Such composite can gradually release iodine when needed, being an efficient, broad-spectrum sanitizers. In this paper, the author attempted to obtain one dimensional PVP- I2 composite nanofibers by electrospinning technique. Benefiting from the high surface area and nanoporous characteristics, the release and controlled-release efficiency as well as antibacterial properties could be enhanced.The PVP-I2 composite nanofibers were obtained by electrospinning the polyvinylprrrolidone-iodine precursor solution, which was prepared with PVP, iodine and anhydrous ethanol as raw material via a sol-gel process. The influence of concentration ratio of PVP to iodine, spinning voltage on the morphology of the products was systematic studied. The study showed that optimized spinning condition was that the mass ratio of PVP is maintained between 10wt.% and 30wt.%. In addition, with the increase of spinning voltage, the diameter of PVP- I2 complex nanofibers diameter decreased.The products were characterized by scanning electron microscope (SEM), infrared spectra (IR), raman spectra (Raman), UV-VIS spectra, X-ray diffraction (XRD). The results demonstrated that the as-electrospun PVP- I2 nanofibers had homogeneous diameters of 400-900 nm and uniform morphology. In the composite nanofibers, chemical bonding existed between polyvinyl pyrrolidone and iodine to form PVP - I2 complex.