• Elastomers and Composites
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• v.7 no.2
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• pp.183-192
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• 1972

As a series of tile studies of EPDM-Polymer blends, tile experiment are concentrated to the investigation of the physical properties of tile EPDM-NR-SBR blends. The results are shown as follows: 1. In blending, tensile strength decreased with increase in EPDM contents, especially the ratio of EPDM/NR-SBR is 75/25. 2. Elongation and tear strength were much influenced by blending, especially the ratio of EPDM/NR-SBR is 50/50. 3. Ozone resistance is much improved after blending. It was effective more than tile ratio of EPDM/NR-SBR is 25/75. 4. Aging resistance is much improved after blending. It was effective more than the ratio of EPDM/NR-SBR is 50/50. 5. Hardness increased with increase in EPDM contents and on the other hand, abrasion resistance decreased.

• Elastomers and Composites
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• v.35 no.2
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• pp.132-137
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• 2000

The cure and physical properties of EPDM foam containing ground rubber and carbon black as filler were studied. The cure time reduced with the addition of filler. This result means reducing the operation time. In case of ground rubber was used, blowing ratio, tensile strength, and elongation were decreased rapidly at above 30 phr. On the other hand, in case of carbon black, they showed similar physical properties until 70 phr was used limited to 30 phr to make a good foam, which should be due to low interfacial interaction between EPDM and ground rubber. All the EPDM foams showed excellent thermal stability.

• Elastomers and Composites
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• v.53 no.3
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• pp.124-130
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• 2018

Recently, microwaves have been used for desulfurization because they can selectively dissociate C-S and S-S bonds present in vulcanized rubber. In this study, we investigated the changes in structural and physical properties of EPDM (Ethylene propylene diene monomer) rubber by irradiating it with microwaves for different durations. The surface chemical composition of the irradiated EPDM rubber was analyzed by FT-IR, XPS, and EDS analyses. It was confirmed by XPS that C-S and S-S S2p peak heights greatly decreased when microwave irradiation was performed for more than 5 min. In the EPDM sample irradiated with microwaves for 10 min, the number of S-O bonds significantly increased owing to oxidation. As the microwave irradiation time was increased, SEM images showed cracks and voids on the EPDM surface. The 20% decomposition temperature of the EPDM rubber sample was investigated by TGA, and it was found to be about $435.23^{\circ}C$ for the EPDM rubber irradiated for 10 min. The crosslinking density of the EPDM rubber was determined by measuring the degree of swelling, and the highest value was observed for the E5 sample irradiated for 5 min. The degree of swelling of the E10 sample irradiated for 10 min was lower than that of the E5 sample. These results indicate that when irradiated with microwaves for more than a certain time, desulfurization occurs and the side chain of the EPDM rubber dissociates and forms additional crosslinking bonds.

• Elastomers and Composites
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• v.53 no.2
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• pp.67-74
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• 2018

Magneto-rheological elastomers (MREs) are smart materials in which the inherent stiffness and damping properties can be changed by the influence of an external magnetic field. The magneto-rheological (MR) effect depends on the orientation characteristics of the dispersed magneto-responsible particles (MRPs) in the matrix. In this study, natural rubber (NR) and ethylene propylene diene rubber (EPDM) were blended and used as a matrix of an MRE. EPDM was pre-cured before blending with NR. The Mooney viscosity, curing characteristics, and mechanical properties were analyzed with various pre-curing conditions of EPDM and the NR/EPDM blend. The results show that excellent mechanical properties of the NR/EPDM blend-based MRE were obtained when the pre-curing time of EPDM was 60 min. The aging property of the NR-based MRE was improved by the introduction of pre-cured EPDM. Also, the anisotropic MRE showed a higher MR effect than that of the isotropic MRE.

• Elastomers and Composites
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• v.40 no.4
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• pp.266-271
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• 2005

In this work, the thermal stability factors, such as the thermal decomposition temperature, decomposition activation energy ($E_d$), and char yield, were measured to investigate the effect of silicone rubber (SR) content on the thermal stabilities of EPDM/SR blends. As a result, the thermal decomposition curve of EPDM/SR blends was similar to the neat EPDM rubber at 10 wt% SR and the thermal decomposition temperature increased above this content. The $E_d$ value of EPDM rubber initially decreased and then was constant above 20 wt% weight losses. The $E_d$ of EPDM/SR blends was higher than that of the neat EPDM rubber and then decreased with increasing the weight loss when the SR content was in the range of 10-20 wt%. Whereas the $E_d$ of the blends was lower than that of the EPDM rubber and then decreased with increasing the weight loss when 30 wt% SR was added. The char yield at $800^{\circ}C$ increased with increasing the SR content, because the decomposition of silane groups in the backbone was capable of forming a silane-rich residue after the initial stage of thermal degradation, which finally prevents further heat transfer and diffusion in the blends.

• Elastomers and Composites
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• v.29 no.2
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• pp.121-130
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• 1994

The physical properties of rubber blend between natural rubber(NR) and ethylene propylene diene terpolymer(EPDM) were investigated as a study of EPDM composite materials. For EPDM/NR blends, the effects of ethylene and diene contents in EPDM, blend ratio, dicumyl peroxide(DCP) curing system on the physical properties, interfacial adhesion force and dynamic crack growth etc. were studied. EPDM/NR blends loaded with carbon black were prepared by mechanical mixing and cured by plate heating cure press. Crosslinking density was measured by swelling method with toluene. The physical properties of all blends were measured with Instron, fatigue to failure(FTF), Demattia flex cracking tester(DMFC), scanning electron microscopy (SEM), etc. As the ethylene and diene contents in EPDM increased, the physical properties, such as dynamic crack growth, adhesion to other component were increased too. Interfacial adhesion force of EPDM/NR blends to dissimilar layer was improved by the use of optimum peroxide curing system.

• Elastomers and Composites
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• v.47 no.2
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• pp.148-155
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• 2012

EPDM, IIR, and BIIR composites were thermally aged and the crosslink density changes were investigated. Crosslink densities of the EPDM composite increased with increasing the aging time and temperature, whereas those of IIR and BIIR composites for long-term aging at high temperatures tended to decrease. Activation energies for the crosslink density changes of the EPDM composite were higher than those of the BIIR one. The experimental results were explained with the number of allylic hydrogens, activation of the zinc complex, the steric hindrance effect, and oxidation of rubber chain.

• Elastomers and Composites
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• v.33 no.4
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• pp.281-289
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• 1998

Tensile properties including Young's modulus and tear strength were measured for four different rubber compounds; natural rubber(NR), styrene-butadiene copolymer(SBR), ethylene-propylene diene monomer (EPDM), and brominated isobutylene-p-methyl-styrene copolymer(BIMS) as a function of temperature and degree of cure. To see the effect of over cure, a measurement was made of the tensile strength and swelling behavior of the over-cured rubber compounds. Young's modulus, E, was found to have linear dependency on the degree of cure for all rubber compounds. EPDM and BIMS showed the highest and lowest slopes, respectively. The slope of NR and SBR lay between EPDM and BIMS. Tear strength, Gc, decreased in the order of NR>BIMS>SBR>EPDM. As the cure time was extended the degree of cure of NR and SBR decreased, while that of BIMS increased. EPDM showed little change in the degree of cure.

• Elastomers and Composites
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• v.6 no.2
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• pp.73-79
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• 1971

As a series of the studies of EPDM-Polymer blends, the experiments are concentrated to the investigation of the physical properties of the EPDM-SBR blends. The results are shown as follows: 1. Tensile strength decreased with increase in EPDM contents and the decreasing value was good results than NR blending. 2. It was found that the aging were much improved after blending and experiments data was good results than NR blending.

• Journal of Environmental Science International
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• v.9 no.6
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• pp.511-515
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• 2000

The purpose of this experiment is to prepare ethylene propylene diene terpolymer(EPDM)/ acrylonitrile butadiene rubber(NBR) blend which represents good environmental resistant properties including favorable oil and ozone resistance. With incorporation of EPDM, NBR and other ingredients, the rubber and chemical additives were mixed by mechanical method such as Banbury mixer and open 2-roll mill. Then rubber vulcanizates were manufactured by hot press and mechanical properties, oil and ozone resistance of the test specimens were measured. The oil resistance and ozone resistance of EPDM and NBR, respectively, is remarkably improved by blending EPDM with NBR. The optimum results of oil and zone resistant characteristics were obtained at EPDM/NBR(=25/75 wt%) composition ratio.