Multi-wall carbon nanotubes (MWNTs) filled polypropylene (PP) nanocomposites were prepared by melt compounding with a twin screw extruder. Polypropylene grafted maleic anhydride (PP-g-MA) was used to promote distribution the carbon nanotubes. The effect of MWNTs-COOH and MWNT addition on the rheological, mechanical and morphological properties of the nanocomposites was assessed for different MWNTs-COOH loadings (i.e.,0.5, 1 and 1.5 wt%). Evidence for hydrogen bonding between maleic anhydride grafted polypropylene and MWNTs-COOH was obtained using FTIR. For linear rheological measurements, the strain amplitude was fixed to 1% . The rheological results showed that the materials experience a fluid–solid transition, beyond which a continuous MWNT network forms throughout the matrix and in turn promotes the reinforcement. On a very large shear rate range ; 100 to 1500 (s -1 ) for all samples with increase shear rate, increase shear stress and decrease shear viscosity. Rheological behavior samples show Herschel bulkley fluid model. When PP-g-MA is added, dynamic moduli and viscosity further increases compared to PP/MWNTs nanocomposite. Results of stress–strain measurement reveal that Young’s modulus increases, while elongation at break decreases with increase in MWNTs-COOH loading. SEM analysis has shown that nanotubes are distributed reasonably uniforml A better distributed good adhesion between the nanotubes and the PP matrix is caused by wrapping of PP-g-MA on MWNTs-COOH. Keywords: surface modification, multi wall carbon nanotubes, polypropylene , rheological behavior and mechanical properties
