Abstract
M.Sc. (Chemistry)
The fabrication of multiwalled carbon nanotube/polyvinyl chloride (PVC) composites and a study of their thermal, fire retardancy and mechanical properties are reported. Triphenylphosphine linked - multiwalled carbon nanotube (TPP-MWCNT) and pristine MWCNT were used. The MWCNT were embedded in the polymer matrix through melt blending and solvent casting. The phosphorylation of the MWCNT and their dispersion in the PVC matrix was characterized by scanning electron microscopy and Raman spectroscopy. Thermal analysis of the nanocomposites by thermal gravimetric analysis (TGA) in both solvent casting and melt bending processes, showed different results when compared with the neat PVC.
The modulus of the MWCNTs / PVC nanocomposites synthesized via melt blending increased, whilst there was a reduction in their tensile strength, indicating a decrease in polymer toughness. The tensile modulus and strength of MWCNTs / PVC nanocomposite synthesized via Solvent casting decreased whilst there was an increase in Tpp-MWCNT/PVC nanocomposite when compared with its counterpart MWCNTs / PVC nanocomposite, indicating an increase in stiffness and strength.
The limited oxygen index (LOI) fire retardant tests of all the neat PVC and its nanocomposites showed no value difference.