| The polyacrylonitrile nanofiber has a great prospect of application because of the special advantages of the nanomaterials. Nowadays, the preparation of the polyacrylonitrile nanofiber is mainly concentrated on the electrospinning, but so far, the electrospinning does not have the unified apparatus, however, it's hard to manufacture nanofibers on a large scale. So, it is important to study the apparatus of the electrospinning polyacrylonitrile nanofiber.In this thesis, we synthesized the polyacrylonitrile with a higher molecular through the solution polymerization, then we prepared the electrospinning solution using the prepared polyacrylonitrile. We made a porous spinneret to solve the problem of mass production, meanwhile, the factor of electrospinning was studied. The best fibers were collected from electrospinning 4 wt% PAN in DMF solutions at 28 kV onto a grounded target which was 15 cm from the spinneret; however, we also found the humidity has an inflection on electrospinning. The final result shows that our spinneret can improve the production efficiency for the higher speed of spinning and easy to be cleaned. On the basis of that, two oriented support systems which named static method collection apparatus and drum assisted dynamic water collection apparatus respectively were made to assist in aligning and the factors of aligning and the mechanism were also researched. Through the experiment we found that although the method of the first apparatus was simply, the stability of the long time electrospinning was not well because of the static electricity. The second apparatus can avoid the effect of the static electricity successfully and the aligning mechanism of it was mainly caused by the flowing water, meanwhile, the drum can assist the collection developed steadily. At last, we got the large aligned fiber mats (about 30 cm X 7 cm) and long bundle of fibers (about 47 cm) in a short time (10 min) by the combination of our spinneret and collection apparatus. |
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