• Elastomers and Composites
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• v.33 no.3
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• pp.159-167
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• 1998

Rubber products are aged like human complexion by the attack of oxygen, ultra violet, ozone, etc.. Aging is very important and also very complicated phenomenon to understand. This may explain the rarity of papers on this subject. In this study, we tried to understand the aging behavior of EPDM compared to that of natural rubber. We also compared the sulfur vulcanized system to the peroxide vulcanized one. In our experiment, the peroxide vulcanizates were more advantageous in aging than the sulfur vulcanizates. The authors belived that this study about the high performance EPDM would be applicable to rubber industry.

• Elastomers and Composites
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• v.43 no.1
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• pp.1-7
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• 2008

Far-infrared vulcanization of ethylene-propylene-diene terpolymer(EPDM) compounds has been studied in comparison with hot air vulcanization. Vulcanization characteristics of EPDM compounds were measured by degree of curing and temperature of specimens in vulcanization process. As a result, degree of curing by far-infrared of EPDM compounds was shown to be higher value than that by hot air at the same vulcanization temperature. Especially, degree of curing by far-infrared on 3 mm thickness of EPDM compounds was increased by two times compared to that by hot air. While the increase of thermal conductivity of EPDM compounds highly improved degree of curing by far-infrared, that hardly improved degree of curing by hot air.

• Journal of Adhesion and Interface
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• v.2 no.4
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• pp.32-38
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• 2001

Effects of the ratio of rubber composition on covulcanization and ozone resistance were studied in this study. Specimens used in this study were rubber compounds(specimen-A) blended with various ratio of NR, SBR, BR, IIR, and EPDM, unsaturated rubber compounds(specimen-B) with NR/BR/SBR, and saturated rubber compounds(specimen-C) with NR/IIR/EPDM. PAD adhesion specimen was prepared from vulcanizing specimen-A and B, and specimen-A and C, respectively. Using same adhesion specimen, peel strength was measured and tested ozone resistance. In specimen-A, peel strength was higher with increasing NR ratio for NR and BR contained blends. In other specimen-A containing NR and SBR, the peel strength was also increased with increasing SBR ratio. NR/BR/IIR/EPDM rubber compounds had also better adhesion property than NR/SBR/IIR/EPDM compounds. As more unsaturated rubber was blended, the peel strength was higher but ozone resistance was worse. Optimum ratio of unsaturated and saturated rubbers for the peel strength and ozone resistance was 60/40.

• Elastomers and Composites
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• v.44 no.3
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• pp.299-307
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• 2009

The effects of reinforcing materials on durability and mechanical properties of V-rib belt were investigated. Cotton fiber and ZnO were used as a filler for CR, and cotton and aramid fiber were used for EPDM rubber compounds. These materials were prepared as a specimen and V-rib belt for heat resistant and mechanical test. High contents of ZnO give improved wear resistance, and higher contents of cotton fiber showed higher durability in high rotation speed but lower wear resistance for CR rubber compounds. Using the aramid and cotton fiber together in EPDM rubber compounds, thermal and wear resistance were improved simultaneously. The material containing EPDM matrix showed better durability and wear resistance than those of containing CR matrix comparing in the same cotton fiber contents.

• Elastomers and Composites
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• v.43 no.2
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• pp.104-112
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• 2008

The ethylene propylene diene terpolymer (EPDM) blends with styrene butadiene rubber (SBR) were prepared from an open 2-roll mill following the conventional rubber blend method, and then cure characteristics, mechanical properties and ozone resistance were subsequently examined. With incorporation of SBR the torque value of the EPDM and SBR blends showed a gradual increase in the cure curve. The maximum torque value was obtained with lowest level at 25wt% of SBR and it was increased linearly with more than 25wt%. As the SBR loading increased scorch time and optimum cure time decreased. Hardness represented a maximum at 50wt% of SBR. However upper and lower than that value it decreased. It was found that the unfavorable characteristics of ozone resistance of pure SBR was significantly improved through the blending of SBR with EPDM.

• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.472-477
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• 2021

The crosslinking behavior of polyhedral oligomeric silsesquioxane (POSS) containing eight acrylate groups in a cage form in ethylene-propylene-diene rubber (EPDM) peroxide crosslinking, the effect on mechanical properties, and the thermal stability were investigated. An EPDM/POSS composite material was prepared by mixing 0 to 12 parts per hundreds of rubber (phr) of POSS per 100 phr of rubber by content and adding a peroxide crosslinking agent. As a result of crosslinking properties, it was found that the acrylate group of POSS was activated by peroxide and improved the peroxide crosslinking efficiency. Although the dispersion stability of POSS in EPDM/POSS composites was poor, the fracture strength, elongation and thermal stability were improved.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.5
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• pp.368-376
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• 2005

Coolant rubber hoses for automobile radiators can be degraded and thus failed due to the influence of contacting stresses of air and coolant liquid under thermal and mechanical loadings. In this study, for EPDM(ethylene-propylene diene monomer) rubber conventionally used as a radiator hose material the aging behaviors of the skin part due to thermo-oxidative and electro-chemical stresses were nondestructively evaluated. Through the thermo-oxidative aging test, it was shown that the surface hardness IRHD(International Rubber Hardness Degrees) of the rubber increased with a considerable reduction of failure strain. On account of the penetration of coolant liquid into the skin part the weight of rubber specimens degraded by electro-chemical degradation(ECD) test increased, whereas their. failure strain and IRHD hardness decreased largely. The penetration of coolant liquid seemed to induce some changes in inner structure and micro hardness distribution of the rubbers. Consequently, EPDM rubbers degraded by thermo-oxidative aging and ECD could be characterized nondestructively by micro-hardness and chemical structure analysis methods.

• Elastomers and Composites
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• v.42 no.1
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• pp.55-58
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• 2007

Thermal Characterization of an EPDM/IIR rubber blend was performed using TG/DTG analysis. While TGA thermograms of a virgin EPDM and IIR showed their own characteristic thermal decomposition curves, that of an EPDM/IIR blend sample showed a characteristic curve, exhibiting both decomposition characteristics of EPDM and IIR. This finding was more clarified from DTG analysis obtained by differentiation of TGA thermograms, being exhibited as two distinct shifted-peaks. Degrees of peak-shift (${\Delta}T$) compared to their original positions were $+25\;^{\circ}C$ for IIR and $-15\;^{\circ}C$ for EPDM, respectively. From these facts, thermal stability of EPDM is considered comparatively better than IIR, and moreover, it can be an evidence for the characteristics of a partial compatibility between EPDM and IIR. It is noteworthy that, if we prepare in advance a calibration curve for the composition about EPDM/IIR blend, it may be possible to analyze quantitatively an EPDM/IIR blend, using comparatively simple TGA experiments as in the present work.

• Elastomers and Composites
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• v.40 no.1
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• pp.59-65
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• 2005

Zinc methacrylate(ZMA) was incorporated into ethylene-propylene diene rubber(EPDM) by direct mixing of the metal salt with the rubber or was in-situ prepared in the rubber matrix through neutralization reaction of zinc oxide(ZnO) and methacrylic acid(MAA). Tensile and tear tests showed that ZMA had a great reinforcing effect for the EPDM. It was also found that ZMA reinforced EPDM vulcanizates can retain their mechanical properties under thermo-oxidative aging. Moreover the incorporation of ZMA induces a substantial improvement in the adhesive strength of the EPDM onto aluminum substrate. The reinforcing effect and an enhancement in adhesion was greatly manifested when the ZMA is in-situ formed with an excess amount of ZnO. The extraordinary improvement in the properties is supposed to be related with the formation of ionic crosslink as well as the degree of dispersion or ZMA domain in the rubber matrix.

• Polymer(Korea)
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• v.37 no.5
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• pp.571-578
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• 2013

Polyamide12 (PA12) is blended with ethylene propylene diene rubber (EPDM) at various compositions in the presence of maleated EPDM (mEPDM) to afford blend materials having the characteristics of thermoplastic elastomer (TPE). The EPDM/PA12 melt-blends are further irradiated with electron-beam (e-beam) at 0~100 kGy dosage, yielding selective crosslinking between EPDM chains while retaining melt-processibility originated from PA12 phase. mEPDM acts as a compatibilizer and affords additional improvements in mechanical properties of the EPDM/PA12 blend. With 25 kGy of e-beam irradiation and mEPDM, the EPDM/PA12 blends successfully exhibit TPE behaviors with reasonable elastomeric and mechanical properties.