Effect of multi-walled carbon nanotube on mechanical and rheological properties of silane modified EPDM rubber

Abstract

Anovel approach for achieving a good dispersion of multi-walled carbon nanotubes (MWCNTs) within the ethylene- propylene diene monomer (EPDM) matrix has been investigated. In this approach, EPDM was modified with vinyltrimethoxysilane (VTMS) through a melt mixing process. In addition, the effect of MWCNTs concentration on the mechanical and rheological properties of the modified EPDM has been studied. The formulated composites exhibited significantly enhanced physical properties even at very low nanotube concentrations. The occurrence of the grafting reaction was confirmed by the Fourier transform infrared spectroscopy (FTIR) peaks at 1070 and 1250 cm-1 according to the Si-O and Si-C vibrations. The state of dispersion of the fillers in the polymer matrix was evaluated through transmission electron microscopy (TEM) and scanning electron microscopy (SEM), in addition surface topology was studied by atomic force microscopy (AFM). The results showed that the VTMS grafted on the EPDM surface improved the dispersion of MWCNTs in the matrix. The rheological characteristics have been studied by rubber process analyzer (RPA). At the low frequencies, the effect of increasing the MWCNT content was significantly high so that the storage modulus (G') and complex viscosity (η*) increased but the difference in storage modulus and complex viscosity values reduced as the frequency was increased. It was found that at concentration of 1.5 wt% of MWCNT, the nanocomposites exhibited remarkable improvements in the mechanical properties such as modulus and tensile strength. Polyolefins J (2016) 3: 69-77