In this study the composites based on ethylene-propylene-diene monomer (EPDM) and multi-walled carbon nanotube (MWCNT) have been prepared by melt compounding. The effects of silane grafting on properties of MWCNT/EPDM composite are investigated. To overcome the problem of non-uniform dispersion of MWCNTs in polymer matrix, Vinyl trimethoxy silane was used as coupling agent. The melt grafting of VTMS onto EPDM chains was done in an internal mixer. The effect of MWCNT concentration on cure characteristics, mechanical, rheological and thermal properties of silane modified EPDM was studied. A comparison with un-modified matrix was also considered. The grafting reaction confirmed by Fourier transform infrared spectroscopy (FT-IR). The state of dispersion of the fillers in the polymer matrix was evaluated through scanning electron microscopy (SEM) and atomic force microscopy (AFM). The rheological characteristics were studied by rubber process analyzer (RPA) and dynamic properties were also investigated by dynamic- mechanical-thermal analysis (DMTA). In addition the mechanical measurement was also done. Moreover, the thermal behavior of VTMS-modified EPDM/MWCNT composite were studied by thermogravimetric analysis (TGA). The results obtained show that the cure time ( ) and scorch time ( ) decreased while maximum torque ( ) and minimum torque ( ) of the modified composites were increased with increasing MWCNT concentration, also results showed that VTMS-grafted onto the EPDM surface improved the dispersion of MWCNTs in matrix. The rheological properties of composites such as storage modulus (G´) and complex viscosity ( ) increased, due to increasing MWCNT content. In addition it was found that due to increasing the amount of MWCNT, composite exhibited superior modulus, tensile strength and hardness whereas lower elongation at break compared to pure and un-modified polymers and it found that the thermal stability of VTMS-modified EPDM/MWCNT was improved. Dynamic mechanical thermal studies reveal a strong rubber-filler interaction in the composite which is manifested in the lowering of tan ? at the glass transition temperature. These finding confirmed the improved interfacial interactions arising from covalent bond between modified EPDM and functional groups of MWCNTs respectively. Keywords : Composite, EPDM, MWCNT, Rheological characteristic, mechanical properties.
