• Elastomers and Composites
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• v.45 no.3
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• pp.152-155
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• 2010

Olefinic thermoplastic elastomer and styrenic thermoplastic elastomer have broad hardness range, high flexibility, low density, and excellent recyclability. But, they are limited in applications due to their low elasticity and low operating temperature. To overcome these problems, olefin/styrene or olefin/$\alpha$-olefin copolymers have been developed. In this review, we described some examples of olefin/styrene or olefin/$\alpha$-olefin copolymer and introduced their properties. Although olefin/styrene or olefin/$\alpha$-olefin copolymer have various weaknesses, they have a great potential in the future.

• Elastomers and Composites
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• v.47 no.4
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• pp.329-335
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• 2012

In this study, we synthesized poly(ethylene-ter-high ${\alpha}$-olefin-ter-p-methylstyrene) using Zr metallocene catalyst/borate type cocatalyst system. Various effects of the high ${\alpha}$-olefin (1-hexene, 1-octene, 1-decene, and 1-dodecene) were observed. The structure and composition of the terpolymers were characterized using $^{13}C$ NMR and $^1H$ NMR. Catalytic activity, polymer yield, molecular weight and molecular weight distribution were analyzed according to the chain length of high ${\alpha}$-olefin. We determined morphology, crystallinity and thermal properties of the terpolymers.

• Macromolecular Research
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• v.12 no.2
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• pp.145-155
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• 2004

Facilitated transport membranes for the separation of olefin/paraffin mixtures have long been of interest in separation membrane science because olefins, such as propylene and ethylene, which are important chemicals in petrochemical industries, are currently separated by energy-intensive cryogenic distillation processes. Recently, solid polymer electrolyte membranes containing silver ions have demonstrated remarkable performance in the separation of olefin/paraffin mixtures in the solid state and, thus, they can be considered as alternatives to cryogenic distillation. Here, we review recent progress, and critical issues affecting in the use of facilitated olefin transport membranes; in particular, we provide a general overview with reference to carrier properties, transport mechanisms, and separation performance.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.2
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• pp.37-43
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• 2014

Exhaust emissions were studied as a function of gasoline olefin composition in two vehicles-MPI and GDi engine equipped vehicles. Three different gasolines were tested which varied in olefin contents-12, 16 and 20 vol%. Exhaust emissions in two vehicles were affected by changes in gasoline olefin composition. Responses to changes in olefins were similar in both vehicles : reducing olefins lowered emissions of NOx and CO. Measured exhaust emissions included total hydrocarbons (THC), oxides of nitrogen (NOx), carbon monooxide(CO), carbon dioxide($CO_2$), formaldehyde, benzene, toluene, xylene, 1,3-butadiene and acetylene.

• Korea lubricating oil industries association bulletin
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• no.73
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• pp.9-21
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• 1995

• Korea lubricating oil industries association bulletin
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• no.74
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• pp.4-15
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• 1996

• Bulletin of the Korean Chemical Society
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• v.22 no.10
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• pp.1156-1158
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• 2001

• Bulletin of the Korean Chemical Society
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• v.14 no.1
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• pp.153-156
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• 1993

• Macromolecular Research
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• v.13 no.3
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• pp.243-252
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• 2005

The effect of the vinyl acetate (VA) content on the thermal, viscoelastic, rheological, morphological and mechanical behaviors in various blends of ethylene-vinyl acetate (EVA)/ethylene-$\alpha$-olefin copolymers was investigated using 28, 22 and $15 mol\%$ of VA in EVA. In the DSC melting and crystallization thermograms of all of the EVA systems blended with ethylene-$\alpha$-olefin copolymers, discrete peaks were observed which were related to the constituents. In the dynamic mechanical thermal analysis, the storage modulus increased with increasing content of ethylene-$\alpha$-olefin copolymers. In addition, the transition regions relating to the tan bpeaks varied with the VA content. The crossover point between G' and G" varied depending on the VA contents, and shear-thinning was more prominent in the EVA/EtBC system. In the SEM investigation, a discrete phase morphology was observed in both the EVA/EtBC and EVA/EtOC blends, but the contrast improved with decreasing VA content. However, the tensile strength and modulus improved, but the elongation at break reduced with decreasing VA content, implying that the ethylene-$\alpha$-olefin copolymers play the role of reinforcing materials. Thus, the EVA and ethylene-$\alpha$-olefin components in the copolymers are immiscible in the molten and solid states, but are nevertheless mechanically compatible.

• Macromolecular Research
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• v.13 no.4
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• pp.297-305
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• 2005

The compatibilizing effect of maleic anhydride (MA) in the immiscible blends of EVA22 (vinyl acetate content 22%)/ethylene-${\alpha}$-olefin copolymers with 1-butene (EtBC) and 1-octene (EtOC)) comonomers was studied. By adding 1, 2, and 3 phr of MA in the presence of dicumylperoxide, the morphology, tensile strength at break, and 100 and 300 % modulus of EVA22/EtBC and EVA22/EtOC blends were significantly enhanced. The melting point and crystallization point depression were observed upon the addition of MA. The changes in the ${\beta}$ transition and glass transition temperature of ethylene-${\alpha}$-olefin copolymers and ethylene-vinyl acetate copolymers, respectively, indicate that MA plays a role of compatibilizer for these immiscible blends. The TGA thermograms, measured from the blends with MA, show that thermal stability is slightly enhanced with MA, indicating that MA acts as a reinforcing agent either by grafting or crosslinking with other copolymers.