• Elastomers and Composites
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• v.58 no.3
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• pp.142-151
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• 2023

In this study, we investigate the thermal and mechanical properties of composites comprising ethylene propylene diene monomer (EPDM) and polybutadiene (PB) obtained using carbon black (CB) as a reinforcing and compatibilizing filler. Owing to the significance of elastomeric materials in various industrial applications, blending of EPDM and PB has emerged as a strategic method to optimize the material properties for specific applications. This study offers insights into the blend composition, its microstructure, and the resulting macroscopic behaviors, focusing on the synergetic effects of composite materials. Furthermore, this study delves into curing and rheological behaviors, crosslink densities, and mechanical, thermal, and elastic properties of the elastomeric composites. Through systematic exploration, we believe that this study will be beneficial to material scientists and engineers working on developing advanced elastomeric composites.

• Elastomers and Composites
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• v.39 no.1
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• pp.36-41
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• 2004

Solid polymer electrolytes were prepared by UV irradiation of the blends consisting of poly(ethylene oxide)(PEO), epoxy diacrylate(EDA) and LiClO_4$. Conductivities of the electrolyte films were measured as a function or blend composition, salt concentration and temperature. The electrolyte having the composition of poly(ethylene oxide) (70% by weight)/epoxy diacrylate (30% by weight) with mole ratio of 10 of ethylene $oxide/Li^+$ exhibited a high ionic conductivity of $1.2{\times}10^{-5} S/cm$ at $25^{\circ}C$. This blend is transparent and shows elastomeric properties. Morphological studies by means of differential scanning calorimetry, X-ray diffraction and polarized optical microscopy indicated that the cured epoxy chains in the blends inhibit the crystallization of poly (ethylene oxide) and thereby induce the blend systems to be completely amorphous in certain compositions.

• Elastomers and Composites
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• v.44 no.3
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• pp.315-322
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• 2009

Influence of blend mode of extender oil on the properties of thermoplastic vulcanizates (TPVs), based on an ethylene-propylene-diene copolymer (EPDM) and a polypropylene (PP), was studied. The EPDM/PP TPVs were prepared in an open roll mill using two different modes in blending sequence of paraffinic oil and phenolic curative, i.e., Oil-Cure and Cure-Oil modes. Degree of cross-linking by gel fraction and properties such as hardness, tensile strength, elongation at break, and melt flow rate were investigated as a function of extender oil content for the two modes. Little influence of the blend mode of extender oil on the degree of cross-linking and mechanical behaviors was observed. However, the use of Cure-Oil mode in the preparation of EPDM/PP TPVs resulted in a marked increase in the level of processability as reflected by melt flow index, as compared to the use of Oil-Cure mode.

• Polymer(Korea)
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• v.36 no.4
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• pp.461-469
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• 2012

The surface modification and characterization of Ar-plasma treated polypropylene (PP) blend are investigated using x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and contact angle measurement. An increase in Ar-plasma treatment time leads to an increase in wettability, oxygen containing polar functional groups, the amount of talc, and surface roughness on the PP blend surface. A careful observation using SEM indicates that there exists a skin layer consisting of only PP component. The difference in viscosity between PP and rubber particles facilities the formation of skin layer. However, it is found that an increase in Ar-plasma treatment time helps to decrease the thickness of skin layer. Additional methodologies for the elimination of skin layer during injection molding are also discussed. The surface modification and morphological alteration induced by Ar-plasma treatment provides a hydrophilic state, followed by the improvement in wettability, on the PP blend surface.

• Elastomers and Composites
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• v.52 no.4
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• pp.242-248
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• 2017

Wet masterbatch (WMB) technology is studied to develop high-content and highly disperse silica-filled compounds. This technology refers to the solidification of surface-modified silica with a rubber solution or latex. Until now, researchs based on styrene butadiene rubber (SBR)/silica WMB has been mainly performed. However, the blending of SBR/silica WMB and BR is not known and is currently under research and development. Therefore, in this study, the BR blending method suitable for emulsion (ESBR)/silica WMB is investigated by measuring their cure characteristics and the mechanical and dynamic viscoelastic properties. As a result, it was confirmed that the blending of ESBR/silica WMB and BR/silica dry masterbatch is most appropriate. However, it showed a disadvantage compared with the conventional mixing method, which was due to the surfactant remained and the sulfuric acid used as the coagulant.

• Elastomers and Composites
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• v.40 no.3
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• pp.204-211
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• 2005

Effect of chlorinated polyethylene(cPE) on the morphology and mechanical properties of isotactic polypropylene(iPP) and nitrile rubber(NBR) blends was investigated. It was found that incorporation of a small amounts of cPE leads to a decrease in domain size of the dispersed phase, and uniform distribution of the dispersed phase in the blends. The PP/NBR/cPE ternary blends showed an improved tensile and tear strength as well as elongation-at-break as compared to binary PP/NBR blends. From the results on morphology and mechanical properties, optimum amount of the cPE is 5-10 wt% with repect to NBR in the blend.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.201-207
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• 2007

The teat cup liner compounds with improved physical property were developed using tri-polymer blend of natural rubber(NR), ethylene propylene diene monomer rubber(EPDM) and butyl rubber, and the changes of the physical properties of compounds were measured under various conditions such as standard, thermal, alkaline detergent and acid solutions aging conditions. The hardness of the new teat cup liner compound 1 was 50 and that of the compound 2 was 51 under standard condition. The tensile strength and elongation of the new compound 1 were $154kgf/cm^2$ and 675% under the standard condition, respectively. Also, those of the new compound 2 were 180 kgf/cm and 634% under the same condition. Their hardness were increased about $2{\sim}6%$ and the tensile strength and elongation were decreased about 10% under the $25^{\circ}C$ water and detergent solutions. Even though the new teat cup liner compounds exhibited so much decreased tensile properties under the $105^{\circ}C$ thermal aged condition, they sustained more stable aged physical properties including tensile strength and elongation than those of imported teat cup liner materials. Consequently, the new teat cup liner compounds would give prolonged lift cycle if they are used as a teat cup liner product.

• Elastomers and Composites
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• v.30 no.3
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• pp.195-206
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• 1995

To modify the NBR rubber roll which has poor abrasion and chemical resistance, NBR/PVC blends were prepared in various composition ratios. First of all, their miscibility and vulcanization characteristics were investigated. Their abrasion and chemical resistant properties and physical properties were also studied. DSC thermograms for NBR/PVC blends show only one Tg in the entire composition range, demonstrating a perfect miscibility. In the vulcanization characteristics tested by rheometer, maximum torque decreases as PVC contents increased. In the investigation of physical properties of NBR/PVC blends, hardness increases and elongation decreases along with the increasing contents of PVC. On the other hands, tensile strength increases with the increasing contents of PVC up to 11.1 wt. %, and then decreases with higher contents of PVC. While the abrasion resistance of NBR/PVC blends was similar to that of NBR itself, the chemical resistance of NBR/PVC blends was superior to that of NBR.

• Elastomers and Composites
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• v.39 no.1
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• pp.51-60
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• 2004

The cure, viscoelastic and mechanical characteristics of organoclay filled NR/BR blends were studied and compared with the properties of carbon black and silica filled NR/BR blends. The nanocomposites with extensive exfoliation state can be fabricated by a solution mixing method. In the composites, the amount of filler content was fixed to 10 phr. Degree of intercalation and exfoliation was characterized by X-ray diffraction (XRD). XRD results indicated exfoliation of the silicate layers into the rubber matrix. While the degree or intercalation and exfoliation is lowered by the conventional mixing method, extensive exfoliation can be obtained by the solution mixing method. It was found that the clay filled NR/BR compound showed better viscoelastic (tan ${\delta}$) and mechanical properties than the carbon black or silica filled NR/BR compounds.

• Elastomers and Composites
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• v.41 no.1
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• pp.3-9
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• 2006

Optimal conditions for preparation of starch/PVA blends were investigated with the consideration of factors that may influence mechanical properties of the blends. Multiplex mixture optimal method as a statistical method were performed and then tensile strength, strain at break, Young's modulus and tear strength of films of the blends were measured to determine the optimal conditions for preparation. The mechanical properties needed for the degradable agricultural mulch were the target of this experiment. Results showed that although the strain at break was a little insufficient, the other properties were very close to the target. This means that the mechanical properties of the film from this blend as a whole are very compatible with those of the reference mulch.