Abstract: The present invention relates to a ligand compound, an organic chromium compound, a catalyst system for ethylene oligomerization, a preparation method thereof, and an ethylene oligomerization method using the same. The catalyst system for ethylene oligomerization according to the present invention is used to prepare a low-density polyethylene in one reactor by using a small amount of comonomers such as alpha-olefin or by using only ethylene without comonomers, because it maintains high catalytic activity and high alpha-olefin selectivity even though supported on a support.

Abstract: The present description relates to an olefin block copolymer with excellences in elasticity, heat resistance, and processability. The olefin block copolymer comprises a plurality of blocks or segments, each comprising an ethylene or propylene repeating unit and an ?-olefin repeating unit at different mole fractions. The olefin block copolymer comprises polymer chains containing 20 to 100 short-chain branches (SCBs) per 1,000 carbon atoms. A point where a first derivative of the number Y of the SCBs per 1,000 carbon atoms of each polymer chain with respect to the molecular weight X of the polymer chain is 0 exists between the minimum and maximum values of the molecular weight X.

Abstract: The present description relates to an olefin block copolymer with excellences in elasticity, heat resistance, and processability. The olefin block copolymer comprises a plurality of blocks or segments, each comprising an ethylene or propylene repeating unit and an ?-olefin repeating unit at different mole fractions. The olefin block copolymer comprises polymer chains containing 20 to 100 short-chain branches (SCBs) per 1,000 carbon atoms. A point where a first derivative of the number Y of the SCBs per 1,000 carbon atoms of each polymer chain with respect to the molecular weight X of the polymer chain is 0 exists between the minimum and maximum values of the molecular weight X.

Abstract: A preparation method of a catalyst for polyolefin polymerization capable of polymerizing low-density polyethylene in a single reactor without separately injecting a comonomer to thereby prepare a final product with a low cost through a more simplified process, a catalyst obtained by the preparation method, and a preparation method of a polyolefin using the catalyst are provided.

Abstract: A preparation method of a catalyst for polyolefin polymerization capable of polymerizing low-density polyethylene in a single reactor without separately injecting a comonomer to thereby prepare a final product with a low cost through a more simplified process, a catalyst obtained by the preparation method, and a preparation method of a polyolefin using the catalyst are provided.

Abstract: The present description relates to olefin block copolymers having excellent elasticity and processability in conjunction with enhanced heat resistance, and to a preparation method thereof. The olefin block copolymers comprise a plurality of blocks or segments that comprise ethylene or propylene repeating units and ?-olefin repeating units at different mole fractions from one another, wherein the block copolymer shows peaks at the 2? of 21.5±0.5° and 23.7±0.5° in a wide-angle x-ray diffraction (WAXD) pattern, and the peak ratio defined by (the peak area at 21.5±0.5°)/(the peak area at 23.7±0.5°) is no more than 3.0.

Abstract: The present invention relates to a method for ethylene oligomerization. According to the method of the present invention, highly active ethylene oligomerization reaction is possible by using a catalyst system including a novel chromium compound exhibiting high activity for ethylene oligomerization reaction, and therefore, polyethylene can be prepared using a small amount of comonomers or using only ethylene without comonomers.

Abstract: The present invention relates to a ligand compound, an organic chromium compound, a catalyst system for ethylene oligomerization, a preparation method thereof, and an ethylene oligomerization method using the same. The catalyst system for ethylene oligomerization according to the present invention is used to prepare a low-density polyethylene in one reactor by using a small amount of comonomers such as alpha-olefin or by using only ethylene without comonomers, because it maintains high catalytic activity and high alpha-olefin selectivity even though supported on a support.

Abstract: The present invention relates to a ligand compound, a chromium compound, and a catalyst system including the same. The catalyst system including the ligand compound or chromium compound according to the present invention exhibits high catalytic activity in ethylene oligomerization reaction, and therefore, polyethylene can be prepared using a small amount of comonomers or using only ethylene without comonomers.

Abstract: The present description relates to an olefin block copolymer with enhanced processability as well as excellences in elasticity and heat resistance, and a preparation method for the same. The olefin block copolymer includes first and second segments, each containing an ethylene or propylene repeating unit and an ?-olefin repeating unit at different mole fractions, where the second segment is dispersed in the form of a closed curve as a dispersed phase on the first segment according to a TEM (Transmission Electron Microscope) image.

Abstract: The present description relates to olefin block copolymers having excellent elasticity and processability in conjunction with enhanced heat resistance, and to a preparation method thereof. The olefin block copolymers comprise a plurality of blocks or segments that comprise ethylene or propylene repeating units and ?-olefin repeating units at different mole fractions from one another, wherein the block copolymer shows peaks at the 2? of 21.5±0.5° and 23.7±0.5° in a wide-angle x-ray diffraction (WAXD) pattern, and the peak ratio defined by (the peak area at 21.5±0.5°)/(the peak area at 23.7±0.5°) is no more than 3.0.

Abstract: The present invention relates to a method for ethylene oligomerization. According to the method of the present invention, highly active ethylene oligomerization reaction is possible by using a catalyst system including a novel chromium compound exhibiting high activity for ethylene oligomerization reaction, and therefore, polyethylene can be prepared using a small amount of comonomers or using only ethylene without comonomers.

Abstract: The present invention relates to a ligand compound, a chromium compound, and a catalyst system including the same. The catalyst system including the ligand compound or chromium compound according to the present invention exhibits high catalytic activity in ethylene oligomerization reaction, and therefore, polyethylene can be prepared using a small amount of comonomers or using only ethylene without comonomers.

Abstract: The present description relates to olefin block copolymers having excellent elasticity and processability in conjunction with enhanced heat resistance, and to a preparation method thereof. The olefin block copolymers comprise a plurality of blocks or segments that comprise ethylene or propylene repeating units and ?-olefin repeating units at different mole fractions from one another, wherein the block copolymer shows peaks at the 2? of 21.5±0.5° and 23.7±0.5° in a wide-angle x-ray diffraction (WAXD) pattern, and the peak ratio defined by (the peak area at 21.5±0.5°)/(the peak area at 23.7±0.5°) is no more than 3.0.

Abstract: The present description relates to an olefin block copolymer with excellences in elasticity, heat resistance, and processability. The olefin block copolymer comprises a plurality of blocks or segments, each comprising an ethylene or propylene repeating unit and an ?-olefin repeating unit at different mole fractions. The olefin block copolymer comprises polymer chains containing 20 to 100 short-chain branches (SCBs) per 1,000 carbon atoms. A point where a first derivative of the number Y of the SCBs per 1,000 carbon atoms of each polymer chain with respect to the molecular weight X of the polymer chain is 0 exists between the minimum and maximum values of the molecular weight X.

Abstract: The present description relates to olefin block copolymers having excellent elasticity and processability in conjunction with enhanced heat resistance, and to a preparation method thereof. The olefin block copolymers comprise a plurality of blocks or segments that comprise ethylene or propylene repeating units and ?-olefin repeating units at different mole fractions from one another, wherein the block copolymer shows peaks at the 2? of 21.5±0.5° and 23.7±0.5° in a wide-angle x-ray diffraction (WAXD) pattern, and the peak ratio defined by (the peak area at 21.5±0.5°)/(the peak area at 23.7±0.5°) is no more than 3.0.

Abstract: The present invention relates to a binuclear metallocene compound having a new structure that is able to offer various selectivities and activities for copolymers, a preparation method thereof, and a method for preparing a polyolefin using the binuclear metallocene compound.