RESUMO
Electrospinning technique is the main method of preparing polymer nanofiber simply, directly and continuously at present. In this work, electrospinning blend solution was prepared by in-situ polymerization using acid-modified multi-walled carbon nanotubes (MWNTs), m-phenylenediamine (MPD) and isophthaloyl chloride (IPC). And then composite nanofibers were prepared by electrospinning. MWNTs played an important role in nanofiber's properties. The effects of MWNTs on the morphology and characterization of the MWNTs/PMIA composite nanofibers were investigated. Scanning electron microscopy (SEM), thermal gravimetric analyzer (TGA), and X-ray diffraction (XRD) were utilized to characterize the MWNTs/PMIA nanofibers morphology and properties. The experimental results indicated that the nanofibers diameter decreased and solution dynamic viscosity increased with increasing MWNTs contents. XRD data demonstrated that PMIA composite nanofibers had the same crystal type as the pure PMIA nanofiber, and crystallinity was improved with increasing MWNTs loading. Transmission electron microscopy (TEM) was used to confirm MWNTs aligned along the axis of composite nanofibers.
RESUMO
The combined use of two techniques namely electrospray and spinning is made use in a highly versatile technique called electrospinning, which produces the diameter of polymer fibers range from nanometer to sub-micron. In this work, we have studied effects of adding LiCl on the morphology and diameter of electrospun poly(ethylene oxide), and we have also evaluated systematically the effect of three important solution parameters on the morphology of electrospun poly(ethylene oxide): molecular weight, solution viscosity and electrical conductivity. We find that molecular weight is strongly correlated with the formation of bead defects in the fibers, the smaller molecular weight, the more beads defect density. As a result, the fibers have beads-in-string structures. Electrical conductivity increases, then decreases as molecular weight increases. Solution viscosity has been found to most strongly affect fiber size, with fibers diameter increasing with increasing solution viscosity according to a power law relationship. In addition, we find evidence that solution viscosity and electrical conductivity affect the interesting morphology of the electrospun nanofibers, and result in doubling and forming membrances phenomena.
