Fabrication and Wettability Characterization of Electrospun Fibrous Nylon 6/Silica Nanocomposites

• Author / Creator

  Chen, Yu

• Electrospinning is a simple and versatile method to fabricate polymeric nanofibers and nanocomposites fibers for a wide range of applications。 Electrospun Nylon 6 nanofiber mats have been used in tissue engineering, filtration and protective clothing. Silica nanoparticles are a type of popular reinforcements for electrospun fibrous nanocomposites due to its tunable size and biocompatibility. Therefore, Nylon 6/silica nanocomposite fibers are studied in this thesis.
  Firstly, the fabrication process is developed. More specifically, the effect of Nylon 6/Formic Acid concentration and silica weight fraction on the solution viscosity and the properties of the end product is studied. In microscopic view, Scanning Electron Microscope was used to characterize the morphology and dimensions of the nanofibers. It was found that the average fiber diameter increased significantly with the increase of Nylon 6 concentration and slightly with the rise of silica weight fraction. Also, when silica weight fraction exceeds a critical value, silica nanoparticles start to agglomerate and silica beads appear from time to time. In macroscopic view, surface roughness and porosity of the mats were measured. The porosity remains unchanged while surface roughness increased by increasing silica weight fraction and decreasing Nylon 6 concentration.
  In the applications such as filtration and tissue engineering, wettability is a very important surface property. Therefore, after the development of the fabrication process, the change of the mats’ wettability with respect to the morphology of the electrospun nanocomposites is investigated. Both the equilibrium contact angle and the dynamic water contact angle was studied. For pristine Nylon 6 nanofiber mats, the equilibrium contact angle was increased with the increase of Nylon 6 concentration. The reason is that higher Nylon 6 concentration gives higher average fiber diameter, which results in lower surface roughness. On the other hand, the dynamic water contact angle curves are similar for the mats made from solutions with different Nylon 6 concentration. When silica nanoparticles are reinforced, the variation of equilibrium contact angle is complicated since silica nanoparticles is hydrophobic, but the particles also increased the surface roughness of the nanofiber mats. It can be concluded that the surface roughness played a more important role than the particles’ hydrophobicity. Dynamic water contact angle is significantly changed by the silica addition. the water drops on the 9% silica reinforced mats were absorbed much quicker than those on pristine Nylon 6 nanofiber mats.

• Subjects / Keywords

  • nanocomposites
  • drop behaviour
  • silica nanoparticles
  • Nylon 6 nanofibers
  • electrospinning
  • wettability

• Graduation date

  Fall 2018

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3NS0MD5X

• License

  Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.