In this work, the influence of compatibilizing method on the phase morphology, mechanical properties and rheological behavior of ternary blends based on polystyrene(PS) /ethylene-propylene-diene terpolymer(EPDM)/ polyamide6 (PA6) was investigated. Two different methods (including in-situ grafted and pre-grafted) were used to compatibilize PS/EPDM/PA6 ternary blends. In the first method, all reactive materials were mixed during mixing, but in the latter, modified EPDM was prepared first and then blended with other components. The chemical reactions occurred during blending followed by Attenuated Fourier Transform Spectroscopy (ATR-FTIR). Mechanical properties investigated by impact and tensile strength measurements. The phase microstructure was observed by Scanning electron spectroscopy (SEM) and the rheological behavior was carried out using a parallel plate rheometer in oscillatory mode. ATR-FTIR results confirmed the grafting and compatibilizing reactions. The morphology size of dispersed phase particles have dramatically changed by increasing EPDM-g-GMA content. The pre-grafted compatibilizing method has revealed finer microstructure than the other method. The modulus of all the ternary compatibilized blends has increased compared to PS/EPDM. In fact, the presence of PA6 introduces a new, more rigid phase in the blend. The pre-grafted compatibilizing method, which uses a compatibilizer content of less than 10 wt.%, is more effective than the in-situ grafted compatibilizing method. This approach results in a finer microstructure and enhanced impact strength. Additionally, it creates a more rigid interface, leading to greater elasticity, which manifests as a semi-plateau in the rheological behavior. In contrast, the in-situ grafted method produces more balanced mechanical properties overall.

The preparation of ethylene propylene diene terpolymer (EPDM)/organoclay nanocomposites by melt blending method was studied. The maleic anhydride modified EPDM oligomer (EPDM-MA) was used as a compatiblizer. The effect of organoclay on structure of nanocomposites was evaluated by X-ray diffraction (XRD). The absence of basal plane peak in XRD results suggests that the EPDM-clay nanocomposits are exfoliated. The mechanical and thermal properties of nanocomposites were examined to observe the influence of the organoclay on the physical properties. The results show remarkable improvement relative to that of EPDM without clay. To prepare EPDM-clay nanocomposites by a straightforward method, a second process was implemented. It was found that the properties of nanocomposites prepared by both methods is nearly the same; however the second method has lower cost and is industrially more practical.

Due to rapid increase in consumption rate of EPDM in rubber industry in the last decade, recycling and reusing of this rubber have attractive and extensive studies. Blending with the other polymers can be an efficient method for reusing of recycled EPDM. In this study, ternary blends of polypropylene (PP), high density polyethylene (HDPE) and mechano-chemical devulcanized EPDM (D-EPDM) were prepared using a laboratory twin-screw extruder. Three levels of D-EPDM (20, 40, 60 wt%) at constant concentration of HDPE (20 wt%) were used. Sulphur dynamic vulcanization was applied on the samples. Mechanical properties such as: tensile properties, compression set, hardness, impact resistance and morphology of samples were studied and compared to samples containing virgin EPDM. Tensile strength and compression set decreased with increase in both D-EPDM and EPDM content in the ternary blend. Dynamic vulcanization improved the mechanical properties and its effect on the samples containing D-EPDM was more  onsiderable. The dominant morphology of both ternary blends was the separate dispersion of HDPE and EPDM (or D-EPDM) in the PP matrix. The D-EPDM formed droplets dispersed in PP matrix similar to the virgin EPDM.

Melt free-radical grafting reactions between ethylene-propylene-dieneterpolymer (EPDM) and glycidyl methacrylate (GMA) were investigated in a batch mixer (170°, C, 60rpm). Effect of dicumylperoxide (DCP) initiator and GMA functionalizing monomer concentrations was studied on the grafted EPDM characteristics. Titration results indicated an increase in the graft degree (GD) and gel content (GC) values with increasing DCP concentration as a result of increasing primary free radical concentration and strengthening cross-linking side reaction. FTIR spectrums confirmed that GMA functionalities have been grafted onto EPDM with appearing carbonyl (C=O) peak. After that, the resultant EPDM-g-GMA was used as compatibilizer in PS(polystyrene)/EPDM/ PA6 (polyamide6) ternary blends. The effect of rubbery compatibilizer on the blend morphology and mechanical properties was studied. The ATR-FTIR spectra of ternary blends, etched to remove unreacted PA6, demonstrated that the compatibilizing reactions occurred during melt blending. By investigating the SEM micrographs it was revealed that the EPDM-g-GMA compatibilizer at the concentration range of 5 wt. % to 15 wt. % changed the size and type of the blend morphology from separated dispersed to multicore-shell morphology. The finest morphology was achieved by using 7. 5 wt. % EPDM-g-GMA. Also, the presence of compatibilizer up to 7. 5 wt. % could improve the tensile modulus, yield stress and impact strength, but a decreasing trend was observed at higher concentration of the compatibilizer.

Soon at the beginning of the last century after it was discovered that carbon black is an active filler in rubbers, it became one of the most important components in manufacturing of rubber products. In this work, the effect of carbon black's type and loading and the structure of rubbers on rate constant and activation energy of the vulcanization were studied by the rheometer. The rubbers for this purpose are ethylene propylene diene monomer (EPDM), with natural rubber (NR), and butadiene rubber (BR). The overall rate of vulcanization is calculated from the kinetic expression of first order vulcanization. The results have showed that carbon black reduces activation energy in all rubbers and increases overall rate of vulcanization. In this case N330 reduces the activation energy and increases the overall rate of vulcanization rather than N660. On the other hand, this research showed that vulcanization rate of EPDM/BR is less than EPDM/ NR. This is as the same trend as the number of allylic hydrogens in the repeat unit of these rubber chains.

The principal objective of this study was to explore the compatibility of a blend of two synthetic elastomers viz., ethylene-propylene-diene rubber (EPDM) and chlorobutyl rubber (CIIR). Various commercial grades of EPDM were blended with a specific grade of CIIR at different proportions. The mechanical properties such as tensile strength, tear strength, ageing resistance, etc. were studied. On the basis of the observed physical properties, two particular grades of EPDM were found to be compatible with CIIR. Differential scanning calorimetry and scanning electron microscopy confirmed the results. Chlorosulphonated polyethylene was added as a compatibilizing agent to overcome the phase separation of the other two incompatible grades of EPDM in blending with CIIR. The results revealed that the addition of compatibilizer greatly improves the compatibility and thereby the properties of the blends.