Copolymerization of ethylene and 1-octene was carried out using a Ziegler-Natta catalyst and the optimization of copolymerization conditions was studied. The optimum polymerization activity was obtained at 60 _C and [Al]:[Ti] molar ratio of 143:1. It was observed that the increase in the comonomer ratio in the feedstock influenced the physical properties of the final copolymer obtained. The results showed a range of crystallinity (Xc) from 68.5% to 34.8% and a range of melting temperature (Tm) from 140 _C to 129 _C for the synthesized copolymers. The viscosity average molecular weight (M̅ v) of the polymers decreased as the polymerization temperature increased, however, by increasing the monomer pressure, the M̅ v of the polymers and the catalyst activity increased. Polymer nanocomposites containing graphene and multi-walled carbon nanotubes with different particle sizes were prepared under the optimum copolymerization conditions. The addition of graphene and multi-walled carbon nanotubes decreased the activity of the catalyst. However, the thermal stability, and crystallinity of the polymers were found to be increased.

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