Preparation, characterization, and compatibilization of novel rubber nanocomposites for mechanical applications: relationship between electrical properties, morphology, and rheology

Abstract

In this paper, a novel rubber nanocomposite containing phenyl-vinyl-methyl-polysiloxane (PVMQ) and ethylene propylene diene monomer (EPDM) was produced during a two-roll mill procedure for mechanical applications. For this purpose, ethylene propylene diene monomer-grafted-maleic anhydride compatibilizer (EPDM-g-MAC) and graphene oxide (GO) was used as a compatibilizer and reinforcements to make a uniform composite. To study mechanical and physical characterizations, dynamic mechanical thermal analysis (DMTA), rheology, morphology, and curing characterizations of nanocomposites were investigated, which showed that compatibilizer makes GO dispersion uniformly. An electrical resistivity test was performed to study the electrical conductivity of the nanocomposites. The results indicate that the samples with higher GO content had a response to the electrical current. The curing study indicates that, by increasing the GO nanoparticles in the presence of EPDM-g-MAC, the curing properties are enhanced as well as mechanical properties by improving the bonding among GO, compatibilizer, and matrix [tensile strength (54%), modulus (68%), elongation-at-break (67%), hardness (81%), and fatigue (51%)]. FE-SEM and TEM images demonstrated that, by increasing GO nanoparticles in the presence of compatibilizer, the mean diameter of EPDM decreased in the substrate, which consequently increased the mechanical properties. The changes in surface temperature were investigated with constant voltage (75 V), which indicates that by increasing GO nanoparticles and electrical conductivity, the surface temperature increased significantly. The results of practical experiments showed good agreement with the theoretical results.