Abstract: A method for manufacturing a gas diffusion layer for a fuel cell wherein carbon nanotubes are impregnated into Korean paper, thereby enhancing electroconductivity, and a gas diffusion layer manufactured thereby. The method for manufacturing a gas diffusion layer for a fuel cell which is to manufacture a gas diffusion layer as a constituent member of a unit cell in a fuel cell, includes a support preparation step of preparing a support with Korean paper; a dispersion preparation step of dispersing a carbon substance in a solvent to form a dispersion, a coating step of coating the support with the dispersion, and a thermal treatment step of thermally treating the dispersion-coated support to fix the carbon substance to the support.

Abstract: A semiconductor memory device is provided. The semiconductor memory device comprises a substrate including a cell region having an active region defined by a cell element isolation layer, a peripheral region near the cell region, and a boundary region between the cell region and the peripheral region. The device includes a word line structure in the substrate and extending in a first direction, a bit line structure on the substrate extending from the cell region to the boundary region in a second direction that crosses the first direction, including first and second cell conductive layers sequentially stacked on the substrate, and a bit line contact between the substrate and the bit line structure and connecting the substrate with the bit line structure. The second cell conductive layer in the boundary region is thicker than the second cell conductive layer in the cell region.

Abstract: The present invention relates to an olefin-based polymer, particularly, to a low-density olefin-based polymer introducing a highly crystalline region and showing high mechanical rigidity.

Abstract: A transition metal compound having a novel structure is disclosed herein. The transition metal compound can have improved structural stability by forming a stable coordination site of a transition metal through controlling a bond angle formed by the amido group of a phenylene bridge, a cyclopentadienyl ring, and a transition metal. The transition metal compound has excellent copolymerization properties and may produce an olefin polymer having a high molecular weight in a ultra low density region.

Abstract: An olefin-based copolymer and method of making the same are disclosed herein. In some embodiments, the olefin-based copolymer includes a repeating unit derived from an alpha-olefin, wherein the alphas-olefin is present in the copolymer at 15 wt % to 45 wt %, wherein the copolymer has a density (d) of 0.85 to 0.89 g/cc, a melt index (MI), measured at 190° C. and 2.16 kg load, of 15 g/10 min to 100 g/10 min, and a hardness defined by Equation 1. The olefin-based copolymer has improved hardness and is highly flowable, and may show improved physical properties of tensile strength, elongation rate and flexural modulus.

Abstract: The present invention provides an ethylene/alpha-olefin copolymer having narrow molecular weight distribution together with a low density and an ultra low molecular weight, minimized number of unsaturated functional groups, and particularly a small amount of vinylidene among the unsaturated functional groups to show excellent physical properties, and a method for preparing the same.

Abstract: The present invention provides an ethylene/alpha-olefin copolymer having narrow molecular weight distribution together with a low density and an ultra low molecular weight, having minimized number of unsaturated functional groups, and having uniform crystallinity, thereby showing excellent physical properties, and a method for preparing the same.

Abstract: An olefin-based copolymer and a method of making the same are disclosed herein. In some embodiments, an olefin-based copolymer has a density (d) of 0.85 to 0.89 g/cc, a melt index (MI), measured at 190° C. and 2.16 kg load, of 15 g/10 min to 100 g/10 min, a number of unsaturated functional groups (total V) per 1,000 carbon atoms of 0.8 or less, a vinylene content, and a vinyl content, wherein the vinylene content, the vinyl content and the total V satisfy (a) vinylene content/total V=0.1 to 0.7 and (b) vinylene content/vinyl content=0.8 to 1.6. The olefin-based copolymer has controlled content and kind of an unsaturated functional group in the olefin-based copolymer and thus, has high flowability, and may show improved physical properties of hardness, flexural strength and tensile strength.

Abstract: The present invention relates to a method for preparing ethylene vinylacetate copolymer that can improve the mechanical strength of copolymer by controlling the polymerization conditions using an autoclave reactor.

Abstract: Provided are an ethylene-vinyl acetate copolymer having a high degree of crosslinking by controlling a temperature difference in an autoclave reactor and an input ratio of an initiator during polymerization, even though a reduced amount of a crosslinking agent is used, and a preparation method thereof.

Abstract: The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.85 to 0.90 g/cc, (2) a melt index (MI, 190° C., 2.16 kg load conditions) ranging from 0.1 g/10 min to 15 g/10 min, (3) the density (d) and the melt temperature (Tm) satisfying Tm (° C.)=a×d?b of Equation 1 (2,350<a<2,500, and 1,900<b<2,100), and (4) a ratio (hardness/Tm) of the hardness (shore A) to the melt temperature (Tm) in a range of 1.0 to 1.3. The olefin-based polymer according to the present invention exhibits excellent anti-blocking properties due to having improved hardness as a low-density olefin-based polymer.

Abstract: The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.850 to 0.865 g/cc, (2) a melt index (MI, 190° C., 2.16 kg load conditions) ranging from 0.1 g/10 min to 3.0 g/10 min, and (3) a soluble fraction (SF) of 10 wt % or more at ?20° C. in cross-fractionation chromatography (CFC), in which a weight average molecular weight (Mw) of the soluble fraction is in a range of 50,000 g/mol to 500,000 g/mol. The olefin-based polymer according to the present invention exhibits improved anti-blocking properties as a low-density olefin-based polymer.

Abstract: The present invention provides an ethylene/alpha-olefin copolymer having narrow molecular weight distribution together with a low density and an ultra low molecular weight, and minimized number of unsaturated functional groups, and in which a comonomer is uniformly present to show excellent physical properties, and a method for preparing the same.

Abstract: The present invention relates to an olefin-based polymer satisfying conditions as follow: (1) a melt index (MI, 190° C., 2.16 kg load conditions) is from 0.1 g/10 min to 10.0 g/10 min, (2) a density (d) is from 0.860 g/cc to 0.880 g/cc, and (3) T(90)?T(50)?50 and T(95)?T(90)?10 are satisfied when measured by a differential scanning calorimetry precise measurement method (SSA). The olefin-based polymer according to the present invention is a low-density olefin-based polymer introducing a highly crystalline region and showing high mechanical rigidity.

Abstract: The present invention relates to a polypropylene-based composite, including (A) polypropylene, and (B) an olefin-based polymer satisfying the following conditions: (1) a melt index (MI, 190° C., 2.16 kg load conditions) is from 0.1 g/10 min to 10.0 g/10 min, (2) a melting temperature when measured by differential scanning calorimetry (DSC) is from 20° C. to 70° C., and (3) a high temperature melting peak is confirmed at 75° C. to 150° C. when measured by a differential scanning calorimetry precise measurement method (SSA), and a total enthalpy of fusion ?H(75) of a corresponding region is 1.0 J/g or more. The polypropylene-based composite of the present invention may show excellent impact strength.

Abstract: An olefin-based polymer satisfying conditions as follow: (1) a melt index (MI, 190° C., 2.16 kg load conditions) is from 0.1 g/10 min to 10.0 g/10 min, (2) a melting temperature when measured by differential scanning calorimetry (DSC) is 20° C. to 70° C., and (3) a high temperature melting peak is confirmed at 75° C. to 150° C. when measured by a differential scanning calorimetry precise measurement method (SSA), and a total enthalpy of fusion ?H(75) of a corresponding region is 1.0 J/g or more. The olefin-based polymer according to the present invention is a low-density olefin-based polymer introducing a highly crystalline region and showing high mechanical rigidity.

Abstract: The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.85 to 0.90 g/cc, (2) a melt index (MI, 190° C., 2.16 kg load conditions) ranging from 0.1 g/10 min to 15 g/10 min, (3) a molecular weight distribution (MWD) in a range of 1.0 to 3.0, and (4) a number average molecular weight (Mn) and a Z+1 average molecular weight (Mz+1) satisfying the Equation 1, {Mn/(Mz+1)}×100>15. The olefin-based polymer according to the present invention is a low-density olefin-based polymer and exhibits excellent tensile strength due to having improved molecular weight as compared to the flow index.

Abstract: The present invention relates to a polypropylene-based composite, including (A) polypropylene, and (B) an olefin-based polymer satisfying the following conditions: (1) a melt index (MI, 190° C., 2.16 kg load conditions) is from 0.1 g/10 min to 10.0 g/10 min, (2) a density (d) is from 0.860 g/cc to 0.880 g/cc, and (3) T(90)-T(50)?50 and T(95)-T(90)?10 are satisfied, wherein T(50), T(90) and T(95) are temperatures at which 50%, 90%, and 95% are melted, respectively, when fractionating a temperature-heat capacity curve from measurement results by the differential scanning calorimetry precise measurement method (SSA). The polypropylene-based composite of the present invention may show excellent impact strength.

Abstract: The present invention relates to a polypropylene-based composite material having improved physical properties including impact strength at low temperature and at room temperature, flexural strength, flexural modulus, etc., and a method for preparing the same.

Abstract: The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.850 g/cc to 0.865 g/cc, (2) a melt index (MI, 190° C., 2.16 kg load conditions) ranging from 0.1 g/10 min to 3.0 g/10 min, (3) a melt temperature (Tm) of 10° C. to 100° C., and (4) a hardness (H, Shore A), the density (d) and the melt temperature (Tm) satisfying Equation 1, and Equation 2 or 3. The olefin-based polymer according to the present invention has low hardness and improved foaming properties, and exhibits improved impact strength at compounding.