Abstract
This work reports on the successful synthesis, characterisation and application of
different forms such as sheets, nanofibers and thin films of polymer nanocomposites.
The nanocomposites morphology and properties as a result of polymer concentration
and organoclay loading are clearly demonstrated. Membrane sheets were successfully
prepared using the phase inversion method. Scanning Electron Microscope (SEM) and
Atomic Force Microscope (AFM) results showed morphology difference as the
polymer concentration is varied. Lower concentration membranes shows a coarser
surface since the polymer chains are freely arranged and the concentration of the
solution is increased the entanglement becomes restricted and showed a more
compact and even membrane surface at higher concentrations. The pristine Poly
(vinyldene fluoride) (PVDF) membranes were found to contain more of the alphaphase
crystallinity polymorph according to X-ray Diffraction (XRD) and Fourirer
Transform Infrared Spectroscopy (FTIR) results. Addition of the organoclay into the
polymer matrix resulted in transforming the alpha-phase polymorph into the betaphase
crystalline polymorph. The surface morphology was also influenced by the
incorporation of the organoclay.
X-ray Photoelectron Spectroscopy (XPS) surface analysis also indicated the presence
of the incorporated organoclays and copper nanoparticles in the nanocomposites. The
Si and Cu peaks are seen emerging in the spectra as a result of their loading. The zeta
potential results showed a change as the organoclay was added into the polymer, with
the higher loading showing a higher potential as compared to the pristine PVDF at
higher pH values as compared to low pH values.
The influenced on polymer concentration on the electrospun nanofibers was observed
through the change in morphology and diameter of the fiber. Lower concentration
showed a wide fiber diameter distribution as the concentration was increased the
change in diameter and morphology observed. Higher concentration showing an...
Ph.D. (Chemistry)