The effect of MWCNTs on the properties of peroxide vulcanized ethylene propylene diene monomer (EPDM) composites

Multiwalled carbon nanotubes (MWCNTs) were incorporated in EPDM matrix in an internal mixer. Characterization of the prepared MWCNTs/EPDM composites using RAMAN spectroscopy reveals a minor deterioration of the CNTs' structure, in terms of intensities ratio of D and G bands (I-D/I-G ratio), probably due to the intensive mixing conditions of internal mixer. The thermal stability of MWCNTs/EPDM composites was improved, as it was observed by thermogravimetric analysis (TGA) results, whereas the glass transition temperature (T-g) remained almost unaffected. In addition, MWCNTs/EPDM composites showed significant improvement in their modulus of elasticity and a decrease in swelling after immersion in benzene, in comparison with the pristine elastomer. The study of dielectric properties for MWCNT's/EPDM nanocomposites determined the percolation threshold between 2 and 3 phr MWCNTs content. Enhancement in electromagnetic interference (EMI) shielding effectiveness of MWCNTs/EPDM composites was also recorded by the increase of filler content in the elastomeric matrix, with the reflectance being the main shielding mechanism. A slight increase in thermal diffusivity and conductivity was observed at EPDM composites with low MWCNTs content (1-5 phr) which became more significant at higher loads (8 & 10 phr).